test: Check error consistently in rpc handlers (#8604)

Co-authored-by: Ayaz Salikhov <[email protected]>

.github/workflows/cargo-audit.yml

@@ -8,6 +8,7 @@ on:
     branches:
       - "develop"
       - "release/*"
+      - "staging/*"
     paths:
       - "crates/**/Cargo.toml"
       - "crates/Cargo.lock"

.github/workflows/on-pr.yml

@@ -243,7 +243,7 @@ jobs:
       - should-run
       - build-test
     # Only run when committing to a PR that targets a release branch.
-    if: ${{ github.repository == 'XRPLF/rippled' && needs.should-run.outputs.go == 'true' && github.event_name == 'pull_request' && startsWith(github.event.pull_request.base.ref, 'release') }}
+    if: ${{ github.repository == 'XRPLF/rippled' && needs.should-run.outputs.go == 'true' && github.event_name == 'pull_request' && startsWith(github.event.pull_request.base.ref, 'release/') }}
     uses: ./.github/workflows/reusable-upload-recipe.yml
     secrets:
       remote_username: ${{ secrets.NEXUS_REMOTE_USERNAME }}

.github/workflows/on-trigger.yml

@@ -1,14 +1,16 @@
 # This workflow runs all workflows to build and test the code on various Linux
 # flavors, as well as on MacOS and Windows, on a scheduled basis, on merge into
-# the 'develop' or 'release*' branches, or when requested manually. Upon pushes
-# to the develop branch it also uploads the libxrpl recipe to the Conan remote.
+# the 'develop', 'release/*' or 'staging/*' branches, or when requested
+# manually. Upon pushes to the develop branch, it also uploads the libxrpl
+# recipe to the Conan remote.
 name: Trigger
 
 on:
   push:
     branches:
       - "develop"
-      - "release*"
+      - "release/*"
+      - "staging/*"
     paths:
       # These paths are unique to `on-trigger.yml`.
       - ".github/workflows/on-trigger.yml"
@@ -62,9 +64,9 @@ on:
   workflow_dispatch:
 
 concurrency:
-  # When a PR is merged into the develop branch it will be assigned a unique
+  # When a PR is merged into the develop branch, it will be assigned a unique
   # group identifier, so execution will continue even if another PR is merged
-  # while it is still running. In all other cases the group identifier is shared
+  # while it is still running. In all other cases, the group identifier is shared
   # per branch, so that any in-progress runs are cancelled when a new commit is
   # pushed.
   group: ${{ github.workflow }}-${{ github.event_name == 'push' && github.ref == 'refs/heads/develop' && github.sha || github.ref }}
@@ -98,7 +100,7 @@ jobs:
       # However, we do not enable ccache for events targeting a release branch,
       # to protect against the rare case that the output produced by ccache is
       # not identical to a regular compilation.
-      ccache_enabled: ${{ github.repository_owner == 'XRPLF' && !startsWith(github.ref, 'refs/heads/release') }}
+      ccache_enabled: ${{ github.repository_owner == 'XRPLF' && !startsWith(github.ref, 'refs/heads/release/') }}
       os: ${{ matrix.os }}
     secrets:
       CODECOV_TOKEN: ${{ secrets.CODECOV_TOKEN }}

.github/workflows/pre-commit.yml

@@ -8,7 +8,8 @@ on:
   push:
     branches:
       - "develop"
-      - "release*"
+      - "release/*"
+      - "staging/*"
   workflow_dispatch:
 
 jobs:

API-CHANGELOG.md

@@ -37,6 +37,7 @@ Version 3.5.0 is not yet released.
 - `channel_verify`: The `channel_id` and `signature` fields now return an `invalidParams` error if the value is not a string. [#7582](https://github.com/XRPLF/rippled/pull/7582)
 - `account_currencies`, `account_nfts`, `account_offers`: A request with more than one problem may now report a different one of them. An invalid `ledger_hash` or `ledger_index` is reported before an invalid or missing `account`. An invalid `limit` or `marker` is reported before `lgrNotFound` or `actNotFound`, and for `account_offers` also before `actMalformed`. A request with a single problem returns the same error as before. [#8561](https://github.com/XRPLF/rippled/pull/8561)
 - `deposit_authorized`: A `credentials` entry that is all zeros (for example `"0"` or 64 `0` characters) now returns a `badCredentials` error instead of looking up a credential that can never exist.
+- `account_info`, `account_lines`, `account_channels`: A request with more than one problem may now report a different one of them. An invalid `ledger_hash` or `ledger_index` is reported before a missing or invalid `account`, or `ident` for `account_info`. For `account_lines`, a `peer` that is not a string, or an invalid `limit` or `marker`, is reported before `lgrNotFound`, `actNotFound` or a malformed `account`, and an invalid `limit` or `marker` also before a malformed `peer`. For `account_channels`, a malformed `account` is reported before `lgrNotFound`, and an invalid `destination_account`, `limit` or `marker` before `lgrNotFound` or `actNotFound`. A request with a single problem returns the same error as before. [#8573](https://github.com/XRPLF/rippled/pull/8573)
 
 ### Bugfixes in 3.5.0
 

cmake/XrplCore.cmake

@@ -297,7 +297,10 @@ if(xrpld)
         VALUE_TYPE "::json::Value"
         VIEW_HEADER "xrpld/rpc/detail/JsonObjectView.hpp"
         HANDLERS
+            account_channels
             account_currencies
+            account_info
+            account_lines
             account_nfts
             account_offers
             book_changes

conan.lock

@@ -3,7 +3,7 @@
     "requires": [
         "zlib/1.3.2#1cb806da49011867778ffb6ac7190fcb%1782392402.122708",
         "xxhash/0.8.3#681d36a0a6111fc56e5e45ea182c19cc%1782392402.420688",
-        "xrpl-rpc-spec/0.1.23#56e8946f5b3fb949a3732e1a51135ca2%1790977482.197086",
+        "xrpl-rpc-spec/0.1.25#2daa763e2d86ccc4ad0a0fa4d1983e9f%1791907455.579992",
         "sqlite3/3.53.0#324ada52333108388a9a6108bfa96734%1782392403.185447",
         "soci/4.0.3#e726491a03468795453f7c83fc924a96%1782392402.679521",
         "snappy/1.1.10#968fef506ff261592ec30c574d4a7809%1782307151.633168",

conanfile.py

@@ -40,7 +40,7 @@ class Xrpl(ConanFile):
         "nudb/2.0.9",
         "openssl/3.6.3",
         "soci/4.0.3",
-        "xrpl-rpc-spec/0.1.23",
+        "xrpl-rpc-spec/0.1.25",
         "zlib/1.3.2",
     ]
 

include/xrpl/basics/Number.h

@@ -352,9 +352,9 @@ class Number final
     using rep = std::int64_t;
     using InternalRep = MantissaRange::rep;
 
-    bool negative_{false};
     InternalRep mantissa_{0};
     int exponent_{std::numeric_limits<int>::lowest()};
+    bool negative_{false};
 
 public:
     // The range for the exponent when normalized
@@ -650,8 +650,12 @@ private:
     shiftExponent(int exponentDelta) const;
 };
 
+// The number class currently has 3 tail padding bytes. If you are adding new
+// members, try to fit them there before expanding the size of the class.
+static_assert(sizeof(Number) == 16);
+
 constexpr Number::Number(bool negative, InternalRep mantissa, int exponent, Unchecked) noexcept
-    : negative_(negative), mantissa_{mantissa}, exponent_{exponent}
+    : mantissa_{mantissa}, exponent_{exponent}, negative_(negative)
 {
 }
 

include/xrpl/ledger/helpers/EscrowHelpers.h

@@ -14,6 +14,7 @@
 #include <xrpl/protocol/AccountID.h>
 #include <xrpl/protocol/Concepts.h>
 #include <xrpl/protocol/Feature.h>
+#include <xrpl/protocol/Fees.h>
 #include <xrpl/protocol/Indexes.h>
 #include <xrpl/protocol/Issue.h>
 #include <xrpl/protocol/Keylet.h>
@@ -27,6 +28,8 @@
 #include <xrpl/protocol/TER.h>
 #include <xrpl/protocol/UintTypes.h>
 
+#include <cstdint>
+
 namespace xrpl {
 
 /**
@@ -560,4 +563,54 @@ escrowUnlockApplyHelper<MPTIssue>(
         journal);
 }
 
+/**
+ * Smart escrow kill switches, driven by the voted FeeSettings.
+ *
+ * Zeroing `bytecodeSizeLimit` stops new uploads while leaving existing escrows
+ * finishable without forcing holders to wait for `CancelAfter`.
+ * Zeroing `gasLimit` stops both.
+ */
+/** @{ */
+inline bool
+isBytecodeUploadDisabled(Fees const& fees)
+{
+    return fees.bytecodeSizeLimit == 0 || fees.gasLimit == 0;
+}
+
+inline bool
+isBytecodeExecutionDisabled(Fees const& fees)
+{
+    return fees.gasLimit == 0;
+}
+/** @} */
+
+/**
+ * Owner count an escrow costs.
+ *
+ *  An escrow costs one increment per started 500 bytes of bytecode, and one
+ *  increment if it carries no bytecode.
+ */
+template <class T>
+int32_t
+calculateAdditionalReserve(T const& finishFunction)
+{
+    static auto constexpr kBytecodeReserveIncrement = 500;
+
+    if (!finishFunction)
+        return 1;
+
+    auto const size = finishFunction->size();
+    if (size == 0)
+    {
+        // LCOV_EXCL_START
+        // Empty Bytecode is refused at create, so no escrow carries it. Ceiling
+        // division would answer 0, which would subtract less than the create added.
+        UNREACHABLE("xrpl::calculateAdditionalReserve : empty Bytecode");
+        return 1;
+        // LCOV_EXCL_STOP
+    }
+
+    return static_cast<int32_t>((size + kBytecodeReserveIncrement - 1) / kBytecodeReserveIncrement);
+}
+
 }  // namespace xrpl

include/xrpl/protocol/Protocol.h

@@ -398,6 +398,11 @@ constexpr std::uint32_t kMaxInvestmentPeriod = std::chrono::seconds{std::chrono:
  */
 constexpr std::uint8_t kMaxAssetCheckDepth = 5;
 
+/**
+ * Maximum length of a Data field in Escrow object that can be updated by WASM code.
+ */
+constexpr std::size_t kMaxWasmDataLength = 1 * 1024;  // 1KB
+
 /**
  * A ledger index.
  */

include/xrpl/protocol/TER.h

@@ -133,7 +133,6 @@ enum TEMcodes : TERUnderlyingType {
     temBAD_MPT,
     temBAD_CIPHERTEXT,
     temINVALID_BYTECODE,
-    temTEMP_DISABLED,
 };
 
 //------------------------------------------------------------------------------
@@ -184,6 +183,8 @@ enum TEFcodes : TERUnderlyingType {
     tefBAD_PATH_COUNT,
     tefNO_BYTECODE,
     tefBYTECODE_NOT_INCLUDED,
+    tefTEMP_DISABLED,
+    tefEXCEEDS_LIMIT,
 };
 
 //------------------------------------------------------------------------------

include/xrpl/tx/invariants/CosignerInvariant.h

@@ -0,0 +1,52 @@
+#pragma once
+
+#include <xrpl/basics/base_uint.h>
+#include <xrpl/beast/utility/Journal.h>
+#include <xrpl/protocol/Keylet.h>
+#include <xrpl/protocol/STLedgerEntry.h>
+#include <xrpl/protocol/STTx.h>
+#include <xrpl/protocol/TER.h>
+#include <xrpl/protocol/XRPAmount.h>
+
+#include <cstdint>
+#include <set>
+#include <vector>
+
+namespace xrpl {
+
+class ReadView;
+
+/**
+ * @brief Invariants for TransactionProposal ledger entries.
+ *
+ * - Only transaction types implementing proposal lifecycle operations may
+ *   create or modify proposals, and a failed one leaves no proposal effect.
+ * - A proposal is deleted only by TransactionProposalCancel or together with
+ *   the Ticket it is keyed to, and a deleted Ticket takes the proposal keyed
+ *   to it along.
+ * - Collected signer arrays remain sorted, unique, and bounded.
+ */
+class ValidTransactionProposal
+{
+    // The Ticket each deleted proposal was keyed to; a proposal may go with
+    // its Ticket, or by Cancel, and no other way.
+    std::vector<uint256> ticketsOfDeletedProposals_;
+    // The proposal each deleted Ticket was keyed to, whether or not one
+    // existed; none may survive its Ticket.
+    std::vector<Keylet> proposalsOfDeletedTickets_;
+    std::set<uint256> deletedTickets_;
+    std::uint32_t created_ = 0;
+    std::uint32_t modified_ = 0;
+    std::uint32_t deleted_ = 0;
+    bool invalidSignerArrays_ = false;
+
+public:
+    void
+    visitEntry(bool isDelete, SLE::ConstRef before, SLE::ConstRef after);
+
+    [[nodiscard]] bool
+    finalize(STTx const& tx, TER result, XRPAmount, ReadView const& view, beast::Journal const& j)
+        const;
+};
+
+}  // namespace xrpl

include/xrpl/tx/invariants/InvariantCheck.h

@@ -9,6 +9,7 @@
 #include <xrpl/protocol/TER.h>
 #include <xrpl/protocol/XRPAmount.h>
 #include <xrpl/tx/invariants/AMMInvariant.h>
+#include <xrpl/tx/invariants/CosignerInvariant.h>
 #include <xrpl/tx/invariants/DirectoryInvariant.h>
 #include <xrpl/tx/invariants/FreezeInvariant.h>
 #include <xrpl/tx/invariants/LoanBrokerInvariant.h>
@@ -483,6 +484,7 @@ using InvariantChecks = std::tuple<
     ValidAmounts,
     ValidMPTTransfer,
     ObjectHasPseudoAccount,
+    ValidTransactionProposal,
     SponsorshipOwnerCountsMatch,
     SponsorshipAccountCountMatchesField>;
 

include/xrpl/tx/transactors/escrow/EscrowCreate.h

@@ -20,11 +20,14 @@ public:
     {
     }
 
+    static bool
+    checkExtraFeatures(PreflightContext const& ctx);
+
     static TxConsequences
     makeTxConsequences(PreflightContext const& ctx);
 
-    static bool
-    checkExtraFeatures(PreflightContext const& ctx);
+    static XRPAmount
+    calculateBaseFee(ReadView const& view, STTx const& tx);
 
     static NotTEC
     preflight(PreflightContext const& ctx);

src/libxrpl/ledger/helpers/ProposalHelpers.cpp

@@ -43,6 +43,9 @@ constexpr auto kProposalTxTypes = std::to_array<TxType>({
 bool
 isValidProposalTxnType(STObject const& proposedTx)
 {
+    if (!proposedTx.isFieldPresent(sfTransactionType))
+        return false;
+
     auto const type = proposedTx.getFieldU16(sfTransactionType);
 
     if (std::ranges::find(kProposalTxTypes, type) != kProposalTxTypes.end())

src/libxrpl/ledger/helpers/SponsorHelpers.cpp

@@ -4,6 +4,7 @@
 #include <xrpl/ledger/ApplyView.h>
 #include <xrpl/ledger/ReadView.h>
 #include <xrpl/ledger/helpers/AccountRootHelpers.h>
+#include <xrpl/ledger/helpers/EscrowHelpers.h>
 #include <xrpl/ledger/helpers/OracleHelpers.h>
 #include <xrpl/ledger/helpers/ProposalHelpers.h>
 #include <xrpl/protocol/AccountID.h>
@@ -319,6 +320,8 @@ getLedgerEntryOwnerCount(SLE const& sle)
             UNREACHABLE("AccountRoots are not supported by object sponsorship.");
             return 0;
             // LCOV_EXCL_STOP
+        case ltESCROW:
+            return calculateAdditionalReserve(sle[~sfBytecode]);
         default:
             return 1;
     }

src/libxrpl/protocol/TER.cpp

@@ -137,6 +137,8 @@ transResults()
         MAKE_ERROR(tefBAD_PATH_COUNT,              "Malformed: Too many paths."),
         MAKE_ERROR(tefNO_BYTECODE,                 "There is no WASM code to run, but a WASM-specific field was included."),
         MAKE_ERROR(tefBYTECODE_NOT_INCLUDED,       "WASM code requires a field that was not included."),
+        MAKE_ERROR(tefTEMP_DISABLED,               "The transaction requires logic that is currently temporarily disabled."),
+        MAKE_ERROR(tefEXCEEDS_LIMIT,               "The transaction exceeds a limit set by fee voting."),
 
         MAKE_ERROR(telLOCAL_ERROR,            "Local failure."),
         MAKE_ERROR(telBAD_DOMAIN,             "Domain too long."),
@@ -209,7 +211,6 @@ transResults()
         MAKE_ERROR(temINVALID_INNER_BATCH,       "Malformed: Invalid inner batch transaction."),
         MAKE_ERROR(temBAD_CIPHERTEXT,            "Malformed: Invalid ciphertext."),
         MAKE_ERROR(temINVALID_BYTECODE,          "Malformed: Provided byte code is invalid."),
-        MAKE_ERROR(temTEMP_DISABLED,             "The transaction requires logic that is currently temporarily disabled."),
 
         MAKE_ERROR(terRETRY,                  "Retry transaction."),
         MAKE_ERROR(terFUNDS_SPENT,            "DEPRECATED."),

src/libxrpl/tx/applySteps.cpp

@@ -31,6 +31,8 @@
 #include <xrpl/protocol/detail/transactions.macro>
 
 #undef TRANSACTION
+#undef TRANSACTION_INCLUDE
+
 #pragma pop_macro("TRANSACTION")
 
 // DO NOT INCLUDE TRANSACTOR HEADER FILES HERE.

src/libxrpl/tx/invariants/CosignerInvariant.cpp

@@ -0,0 +1,225 @@
+#include <xrpl/tx/invariants/CosignerInvariant.h>
+
+#include <xrpl/basics/Log.h>
+#include <xrpl/basics/base_uint.h>
+#include <xrpl/beast/utility/Journal.h>
+#include <xrpl/ledger/ReadView.h>
+#include <xrpl/protocol/AccountID.h>
+#include <xrpl/protocol/Feature.h>
+#include <xrpl/protocol/Indexes.h>
+#include <xrpl/protocol/Keylet.h>
+#include <xrpl/protocol/LedgerFormats.h>
+#include <xrpl/protocol/Protocol.h>
+#include <xrpl/protocol/SField.h>
+#include <xrpl/protocol/STArray.h>
+#include <xrpl/protocol/STLedgerEntry.h>
+#include <xrpl/protocol/STObject.h>
+#include <xrpl/protocol/STTx.h>
+#include <xrpl/protocol/SeqProxy.h>
+#include <xrpl/protocol/TER.h>
+#include <xrpl/protocol/TxFormats.h>
+#include <xrpl/protocol/XRPAmount.h>
+
+#include <algorithm>
+#include <array>
+#include <cstddef>
+#include <cstdint>
+#include <optional>
+
+namespace xrpl {
+
+namespace {
+
+bool
+validSignerArray(STArray const& signers, std::size_t limit, SField const& elementName)
+{
+    if (signers.size() > limit)
+        return false;
+
+    std::optional<AccountID> previous;
+    for (auto const& signer : signers)
+    {
+        if (signer.getFName() != elementName || !signer.isFieldPresent(sfAccount))
+            return false;
+
+        auto const account = signer.getAccountID(sfAccount);
+        if (previous && account <= *previous)
+            return false;
+        previous = account;
+    }
+    return true;
+}
+
+bool
+validNestedSigners(STObject const& signature)
+{
+    return !signature.isFieldPresent(sfSigners) ||
+        validSignerArray(signature.getFieldArray(sfSigners), STTx::kMaxMultiSigners, sfSigner);
+}
+
+bool
+validSignerArrays(STObject const& proposedTx)
+{
+    if (!validNestedSigners(proposedTx))
+        return false;
+
+    for (auto const* field :
+         std::array<SField const*, 2>{&sfCounterpartySignature, &sfSponsorSignature})
+    {
+        if (proposedTx.isFieldPresent(*field) &&
+            !validNestedSigners(proposedTx.getFieldObject(*field)))
+            return false;
+    }
+
+    if (!proposedTx.isFieldPresent(sfBatchSigners))
+        return true;
+
+    auto const& batchSigners = proposedTx.getFieldArray(sfBatchSigners);
+    if (!validSignerArray(batchSigners, kMaxBatchSigners, sfBatchSigner))
+        return false;
+
+    return std::ranges::all_of(
+        batchSigners, [](auto const& batchSigner) { return validNestedSigners(batchSigner); });
+}
+
+// The Ticket a proposal is keyed to: the one its proposed transaction spends.
+uint256
+proposalTicketKey(SLE const& proposal)
+{
+    auto const& proposedTx = proposal.getFieldObject(sfProposedTransaction);
+    return keylet::ticket(
+               proposedTx.getAccountID(sfAccount),
+               SeqProxy::rawTicket(proposedTx.getFieldU32(sfTicketSequence)))
+        .key;
+}
+
+}  // namespace
+
+void
+ValidTransactionProposal::visitEntry(bool isDelete, SLE::ConstRef before, SLE::ConstRef after)
+{
+    // `after` is always present (on deletion it holds the final state), so it
+    // alone determines the entry type. LedgerEntryTypesMatch owns malformed
+    // type transitions; skip them rather than read one side with the other's
+    // schema.
+    if (!after || (before && before->getType() != after->getType()))
+        return;
+
+    auto const type = after->getType();
+
+    // Consuming a Ticket deletes the proposal keyed to it (XLS-0103 §4.5).
+    // Remember each Ticket that went, so finalize can tell a proposal deleted
+    // with its Ticket from one that simply vanished, and the proposal each
+    // Ticket was keyed to, so finalize can check that none stayed behind.
+    if (type == ltTICKET)
+    {
+        if (isDelete)
+        {
+            deletedTickets_.insert(after->key());
+            proposalsOfDeletedTickets_.push_back(
+                keylet::txProposal(
+                    after->getAccountID(sfAccount), after->getFieldU32(sfTicketSequence)));
+        }
+        return;
+    }
+
+    if (type != ltTRANSACTION_PROPOSAL)
+        return;
+
+    if (!before)
+    {
+        ++created_;
+    }
+    else if (isDelete)
+    {
+        ++deleted_;
+        ticketsOfDeletedProposals_.push_back(proposalTicketKey(*before));
+    }
+    else
+    {
+        ++modified_;
+    }
+
+    // A live proposal's signer lists must stay submittable: within size
+    // limits, sorted by account, and free of duplicates.
+    if (!isDelete && !validSignerArrays(after->getFieldObject(sfProposedTransaction)))
+        invalidSignerArrays_ = true;
+}
+
+bool
+ValidTransactionProposal::finalize(
+    STTx const& tx,
+    TER result,
+    XRPAmount,
+    ReadView const& view,
+    beast::Journal const& j) const
+{
+    if (!view.rules().enabled(featureCosign))
+        return true;
+
+    if (invalidSignerArrays_)
+    {
+        JLOG(j.fatal()) << "Invariant failed: TransactionProposal signer arrays are not canonical.";
+        return false;
+    }
+
+    // A proposal leaves the ledger in two ways (XLS-0103 §4.5): a
+    // TransactionProposalCancel deletes the proposal it names, and consuming
+    // the Ticket a proposal is keyed to deletes the proposal with it, whether
+    // the proposed transaction executed (or failed with a claimed-fee tec) or
+    // AccountDelete swept the target's Tickets.
+    std::uint32_t deletedWithTicket = 0;
+    for (auto const& ticketKey : ticketsOfDeletedProposals_)
+    {
+        if (deletedTickets_.contains(ticketKey))
+            ++deletedWithTicket;
+    }
+
+    bool const succeeded = isTesSuccess(result);
+    bool effectsMatch = false;
+    if (tx.getTxnType() == ttTRANSACTION_PROPOSAL_CREATE)
+    {
+        effectsMatch = created_ == (succeeded ? 1u : 0u) && modified_ == 0 && deleted_ == 0;
+    }
+    else if (tx.getTxnType() == ttTRANSACTION_PROPOSAL_CANCEL)
+    {
+        // A Cancel deletes one proposal and nothing else. It cannot
+        // spend a reserved Ticket, so no proposal goes with its Ticket here.
+        effectsMatch = created_ == 0 && modified_ == 0 && deletedWithTicket == 0 &&
+            deleted_ == (succeeded ? 1u : 0u);
+    }
+    else
+    {
+        // Any other transaction deletes a proposal only together with its
+        // Ticket, and modifies at most one, only as a successful
+        // SponsorshipTransfer.
+        // TODO: extend this when TransactionProposalSign is implemented.
+        std::uint32_t const modifiable =
+            tx.getTxnType() == ttSPONSORSHIP_TRANSFER && succeeded ? 1 : 0;
+        effectsMatch = created_ == 0 && modified_ <= modifiable && deleted_ == deletedWithTicket;
+    }
+
+    if (!effectsMatch)
+    {
+        JLOG(j.fatal())
+            << "Invariant failed: TransactionProposal changes do not match transaction result.";
+        return false;
+    }
+
+    // The other direction of the deletion rule: ticketDelete deletes the
+    // proposal keyed to a Ticket along with it (XLS-0103 §4.5), so no
+    // proposal may outlive its Ticket, orphaned on a key that can no longer
+    // be spent.
+    bool const orphaned = std::ranges::any_of(
+        proposalsOfDeletedTickets_, [&view](Keylet const& keylet) { return view.exists(keylet); });
+    if (orphaned)
+    {
+        JLOG(j.fatal())
+            << "Invariant failed: TransactionProposal outlived the Ticket it is keyed to.";
+        return false;
+    }
+
+    return true;
+}
+
+}  // namespace xrpl

src/libxrpl/tx/invariants/InvariantCheck.cpp

@@ -935,8 +935,12 @@ ValidClawback::finalize(
                         return !mptV2Enabled;
                     }
 
+                    // IOU balances keep 16 significant digits, so a clawback
+                    // much smaller than the balance changes it by a rounded
+                    // amount, possibly zero. Compare with the same rounded
+                    // subtraction the balance update performs.
                     if (*afterBalance > *beforeBalance ||
-                        (*beforeBalance - *afterBalance) != std::min(*beforeBalance, clawAmount))
+                        *afterBalance != *beforeBalance - std::min(*beforeBalance, clawAmount))
                     {
                         JLOG(j.fatal())
                             << "Invariant failed: trustline clawback balance change is invalid";

src/libxrpl/tx/paths/BookStep.cpp

@@ -254,6 +254,15 @@ private:
         TAmounts<TIn, TOut> const& stepAmt,
         TOut const& ownerGives) const;
 
+    template <template <typename, typename> typename Offer>
+    void
+    tryConsumeOffer(
+        PaymentSandbox& sb,
+        Offer<TIn, TOut>& offer,
+        TAmounts<TIn, TOut> const& ofrAmt,
+        TAmounts<TIn, TOut> const& stepAmt,
+        TOut const& ownerGives) const;
+
     // If clobQuality is available and has a better quality then return nullopt,
     // otherwise if amm liquidity is available return AMM offer adjusted based
     // on clobQuality.
@@ -810,10 +819,11 @@ BookStep<TIn, TOut, TDerived>::forEachOffer(
         auto const amtIn = [&](TIn const& in) { return capInMPT && *maxIn_ < in ? *maxIn_ : in; };
         try
         {
-            // All arithmetic in this block runs before the offer is consumed.
             // A crafted MPTokensV2 offer can overflow while transfer rates or
-            // crossing limits are applied; remove that unusable offer instead
-            // of letting it persist as a tecINTERNAL source.
+            // crossing limits are applied, here or in the callback's
+            // limitStepIn()/limitStepOut(); remove that unusable offer instead
+            // of letting it persist as a tecINTERNAL source. Overflows while
+            // consuming the offer are handled by tryConsumeOffer().
             stpAmt.in = mulRatio(amtIn(ofrAmt.in), ofrInRate, QUALITY_ONE, /*roundUp*/ true);
 
             // owner pays the transfer fee. An MPT gross-up that doesn't fit in
@@ -941,16 +951,9 @@ BookStep<TIn, TOut, TDerived>::forEachOffer(
                 removeOffer("Removing offer with overflowing amount calculation");
                 return true;
             }
-            // An overflow can only be produced by a crafted MPT offer, and MPT
-            // offers require featureMPTokensV2 (enforced at OfferCreate
-            // preflight). So the amendment is always enabled when we get here
-            // and this legacy re-throw is unreachable in practice.
-            // LCOV_EXCL_START
-            XRPL_ASSERT(
-                sb.rules().enabled(featureMPTokensV2),
-                "xrpl::BookStep::forEachOffer : overflow implies MPTokensV2");
+            // Legacy behavior: the exception escapes flow() and the
+            // transaction fails with tecINTERNAL.
             throw;
-            // LCOV_EXCL_STOP
         }
     };
 
@@ -991,6 +994,32 @@ BookStep<TIn, TOut, TDerived>::forEachOffer(
     return {offers.permToRemove(), counter.count()};
 }
 
+template <class TIn, class TOut, class TDerived>
+template <template <typename, typename> typename Offer>
+void
+BookStep<TIn, TOut, TDerived>::tryConsumeOffer(
+    PaymentSandbox& sb,
+    Offer<TIn, TOut>& offer,
+    TAmounts<TIn, TOut> const& ofrAmt,
+    TAmounts<TIn, TOut> const& stepAmt,
+    TOut const& ownerGives) const
+{
+    try
+    {
+        // Under MPTokensV2, an overflow while consuming the offer fails the
+        // strand instead of being handled by forEachOffer().
+        consumeOffer(sb, offer, ofrAmt, stepAmt, ownerGives);
+    }
+    catch (std::overflow_error const&)
+    {
+        if (sb.rules().enabled(featureMPTokensV2))
+        {
+            Throw<FlowException>(tecINTERNAL, "Overflow while consuming offer");
+        }
+        throw;
+    }
+}
+
 template <class TIn, class TOut, class TDerived>
 template <template <typename, typename> typename Offer>
 void
@@ -1192,7 +1221,7 @@ BookStep<TIn, TOut, TDerived>::revImp(
             savedOuts.insert(stpAmt.out);
             result = TAmounts<TIn, TOut>(sum(savedIns), sum(savedOuts));
             remainingOut = out - result.out;
-            this->consumeOffer(sb, offer, ofrAmt, stpAmt, ownerGives);
+            this->tryConsumeOffer(sb, offer, ofrAmt, stpAmt, ownerGives);
             // return true b/c even if the payment is satisfied,
             // we need to consume the offer. An offer limited by what the
             // issuer can issue is not consumed, though: its remainder is still
@@ -1224,7 +1253,7 @@ BookStep<TIn, TOut, TDerived>::revImp(
         savedOuts.insert(remainingOut);
         result.in = sum(savedIns);
         result.out = out;
-        this->consumeOffer(sb, offer, ofrAdjAmt, stpAdjAmt, ownerGivesAdj);
+        this->tryConsumeOffer(sb, offer, ofrAdjAmt, stpAdjAmt, ownerGivesAdj);
 
         // Explicitly check whether the offer is funded.  Given that we have
         // (stpAmt.out > remainingOut), it's natural to assume the offer
@@ -1408,7 +1437,7 @@ BookStep<TIn, TOut, TDerived>::fwdImp(
         savedOuts = std::move(savedOutsAdj);
         result = resultAdj;
         remainingIn = in - result.in;
-        this->consumeOffer(sb, offer, ofrAdjAmt, stpAdjAmt, ownerGivesAdj);
+        this->tryConsumeOffer(sb, offer, ofrAdjAmt, stpAdjAmt, ownerGivesAdj);
 
         // When the mantissas of two iou amounts differ by less than ten, then
         // subtracting them leaves a result of zero. This can cause the check
@@ -1512,6 +1541,18 @@ BookStep<TIn, TOut, TDerived>::check(StrandContext const& ctx) const
         return temBAD_PATH;
     }
 
+    // An issuer paying with its own MPT issues it into the first book. A
+    // holder-sourced strand records the MPT in the first MPTEndpointStep and
+    // so rejects a later book that outputs it again; do the same here. The
+    // step after such a book issues the MPT a second time and the payment
+    // engine cannot keep the two within MaximumAmount once StrandFlow
+    // rebuilds the sandbox on a limiting step.
+    if (ctx.isFirst && book_.in.holds<MPTIssue>() && book_.in.getIssuer() == ctx.strandSrc &&
+        ctx.view.rules().enabled(featureMPTokensV2))
+    {
+        ctx.seenDirectAssets[0].insert(book_.in);
+    }
+
     // Do not allow two books to output the same issue. This may cause offers on
     // one step to unfund offers in another step.
     if (!ctx.seenBookOuts.insert(book_.out).second ||

src/libxrpl/tx/paths/MPTEndpointStep.cpp

@@ -6,6 +6,7 @@
 #include <xrpl/beast/utility/instrumentation.h>
 #include <xrpl/core/ServiceRegistry.h>
 #include <xrpl/ledger/PaymentSandbox.h>
+#include <xrpl/ledger/View.h>
 #include <xrpl/ledger/helpers/MPTokenHelpers.h>
 #include <xrpl/ledger/helpers/TokenHelpers.h>
 #include <xrpl/protocol/AccountID.h>
@@ -874,15 +875,18 @@ MPTEndpointStep<TDerived>::check(StrandContext const& ctx) const
 
     // pure issue/redeem can't be frozen (issuer/holder)
     // For the first step: check global freeze of the step's own asset.
-    // For the last step: check only the per-holder MPToken lock.
+    // For the last step: check only the per-holder lock.
     // Global freeze of the deliver asset is not checked here
     // because MPT semantics allow issuer<->holder transfers even when globally
     // locked — only holder-to-holder DEX paths are restricted.
+    // For both steps: a vault share inherits the freeze of the vault's
+    // underlying asset.
     if (!(ctx.isLast && ctx.isFirst))
     {
         auto const& account = ctx.isFirst ? src_ : dst_;
         bool const frozen = (ctx.isFirst && isGlobalFrozen(ctx.view, mptIssue_)) ||
-            isIndividualFrozen(ctx.view, account, mptIssue_);
+            isIndividualFrozen(ctx.view, account, mptIssue_) ||
+            isVaultPseudoAccountFrozen(ctx.view, account, mptIssue_, 0);
         if (frozen)
             return terLOCKED;
     }

src/libxrpl/tx/transactors/escrow/EscrowCancel.cpp

@@ -110,11 +110,16 @@ EscrowCancel::doApply()
     auto const sle = ctx_.view().peek(keylet::account(account));
     STAmount const amount = escrow->getFieldAmount(sfAmount);
 
+    auto const reserveToSubtract = calculateAdditionalReserve((*escrow)[~sfBytecode]);
+
     // The return can re-create a holding the owner deleted while the escrow
     // was pending; the removed escrow must not be counted against its reserve.
     bool const recycleReserve = ctx_.view().rules().enabled(fixCleanup3_4_0);
     if (recycleReserve)
-        decreaseOwnerCountForObject(ctx_.view(), sle, escrow.mutableRawSle(), 1, ctx_.journal);
+    {
+        decreaseOwnerCountForObject(
+            ctx_.view(), sle, escrow.mutableRawSle(), reserveToSubtract, ctx_.journal);
+    }
 
     // Transfer amount back to the owner
     if (isXRP(amount))
@@ -160,7 +165,10 @@ EscrowCancel::doApply()
     }
 
     if (!recycleReserve)
-        decreaseOwnerCountForObject(ctx_.view(), sle, escrow.mutableRawSle(), 1, ctx_.journal);
+    {
+        decreaseOwnerCountForObject(
+            ctx_.view(), sle, escrow.mutableRawSle(), reserveToSubtract, ctx_.journal);
+    }
 
     // Remove escrow from ledger
     escrow.erase();

src/libxrpl/tx/transactors/escrow/EscrowCreate.cpp

@@ -4,8 +4,8 @@
 #include <xrpl/basics/chrono.h>
 #include <xrpl/beast/utility/Zero.h>
 #include <xrpl/conditions/Condition.h>
-#include <xrpl/core/ServiceRegistry.h>
 #include <xrpl/ledger/ApplyView.h>
+#include <xrpl/ledger/ReadView.h>
 #include <xrpl/ledger/View.h>
 #include <xrpl/ledger/entries/EscrowEntry.h>
 #include <xrpl/ledger/helpers/AccountRootHelpers.h>
@@ -16,6 +16,7 @@
 #include <xrpl/protocol/AccountID.h>
 #include <xrpl/protocol/Concepts.h>
 #include <xrpl/protocol/Feature.h>
+#include <xrpl/protocol/Fees.h>
 #include <xrpl/protocol/Indexes.h>
 #include <xrpl/protocol/Issue.h>
 #include <xrpl/protocol/Keylet.h>
@@ -130,6 +131,19 @@ escrowCreatePreflightHelper<MPTIssue>(PreflightContext const& ctx)
     return tesSUCCESS;
 }
 
+XRPAmount
+EscrowCreate::calculateBaseFee(ReadView const& view, STTx const& tx)
+{
+    XRPAmount txnFees{Transactor::calculateBaseFee(view, tx)};
+    if (tx.isFieldPresent(sfBytecode))
+    {
+        // Ten base fees in all: `Transactor::calculateBaseFee` charges one,
+        // this adds nine. Plus 5 drops per byte.
+        txnFees += 9 * view.fees().base + 5 * tx[sfBytecode].size();
+    }
+    return txnFees;
+}
+
 NotTEC
 EscrowCreate::preflight(PreflightContext const& ctx)
 {
@@ -161,12 +175,19 @@ EscrowCreate::preflight(PreflightContext const& ctx)
         ctx.tx[sfCancelAfter] <= ctx.tx[sfFinishAfter])
         return temBAD_EXPIRATION;
 
+    if (ctx.tx.isFieldPresent(sfBytecode) && !ctx.tx.isFieldPresent(sfCancelAfter))
+        return temBAD_EXPIRATION;
+
     // In the absence of a FinishAfter, the escrow can be finished
     // immediately, which can be confusing. When creating an escrow,
     // we want to ensure that either a FinishAfter time is explicitly
     // specified or a completion condition is attached.
-    if (!ctx.tx[~sfFinishAfter] && !ctx.tx[~sfCondition])
+    if (!ctx.tx[~sfFinishAfter] && !ctx.tx[~sfCondition] && !ctx.tx[~sfBytecode])
+    {
+        JLOG(ctx.j.debug()) << "Must have at least one of FinishAfter, "
+                               "Condition, or Bytecode.";
         return temMALFORMED;
+    }
 
     if (auto const cb = ctx.tx[~sfCondition])
     {
@@ -182,6 +203,33 @@ EscrowCreate::preflight(PreflightContext const& ctx)
         }
     }
 
+    if (ctx.tx.isFieldPresent(sfData))
+    {
+        if (!ctx.tx.isFieldPresent(sfBytecode))
+        {
+            JLOG(ctx.j.debug()) << "EscrowCreate with Data requires Bytecode";
+            return temMALFORMED;
+        }
+        auto const data = ctx.tx.getFieldVL(sfData);
+        if (data.size() > kMaxWasmDataLength)
+        {
+            JLOG(ctx.j.debug()) << "EscrowCreate.Data bad size " << data.size();
+            return temMALFORMED;
+        }
+    }
+
+    // amendment was checked by checkExtraFeatures
+    if (ctx.tx.isFieldPresent(sfBytecode))
+    {
+        auto const code = ctx.tx.getFieldVL(sfBytecode);
+        // Protocol ceiling only; `preflight` has no view.
+        if (code.empty() || code.size() > kMaxBytecodeSizeLimit)
+        {
+            JLOG(ctx.j.debug()) << "EscrowCreate.Bytecode bad size " << code.size();
+            return temMALFORMED;
+        }
+    }
+
     return tesSUCCESS;
 }
 
@@ -216,6 +264,30 @@ EscrowCreate::preclaim(PreclaimContext const& ctx)
             !isTesSuccess(ret))
             return ret;
     }
+
+    // The limits are voted, so they can change between ledgers. A `tef`, unlike
+    // a `tem`, does not mark the transaction bad for the hold time.
+    if (ctx.tx.isFieldPresent(sfBytecode))
+    {
+        auto const& fees = ctx.view.fees();
+        if (isBytecodeUploadDisabled(fees))
+        {
+            JLOG(ctx.j.debug()) << "WASM runtime deactivated by fee voting";
+            return tefTEMP_DISABLED;
+        }
+
+        auto const code = ctx.tx.getFieldVL(sfBytecode);
+        if (code.size() > fees.bytecodeSizeLimit)
+        {
+            JLOG(ctx.j.debug()) << "EscrowCreate.Bytecode over voted limit " << code.size();
+            return tefEXCEEDS_LIMIT;
+        }
+
+        // TODO(SmartEscrow): screen the module itself here - that it compiles,
+        // and that it imports and exports what the engine can serve - once the
+        // WASM engine lands. Until then any blob of the right size is taken.
+    }
+
     return tesSUCCESS;
 }
 
@@ -236,6 +308,7 @@ EscrowCreate::doApply()
 
     // Check reserve and funds availability
     STAmount const amount{ctx_.tx[sfAmount]};
+    auto const reserveToAdd = calculateAdditionalReserve(ctx_.tx[~sfBytecode]);
 
     auto const balance = sle->getFieldAmount(sfBalance).xrp();
     // First check: whoever is on the hook for the new owner increment
@@ -243,8 +316,8 @@ EscrowCreate::doApply()
     // validates the sponsor's reserve + remaining credit. When
     // unsponsored this hits the source branch and validates the
     // source's pre-lock balance against base + (currentOC+1)*increment.
-    if (auto const ret =
-            checkReserve(ctx_.getApplyViewContext(), sle, balance, {.ownerCountDelta = 1}, j_);
+    if (auto const ret = checkReserve(
+            ctx_.getApplyViewContext(), sle, balance, {.ownerCountDelta = reserveToAdd}, j_);
         !isTesSuccess(ret))
         return ret;
 
@@ -258,11 +331,15 @@ EscrowCreate::doApply()
         // checkReserve) because that helper diverts to the sponsor's balance
         // when a sponsor is present and would ignore the source's post-lock
         // balance entirely. ownerCountDelta differs by case:
-        // - sponsored:   0  — sponsor covers the new owner increment, so the
-        //                source only owes reserve for its current owners.
-        // - unsponsored: 1  — source owes reserve including the new increment.
+        // - sponsored:   0            — sponsor covers the new owner increment, so
+        //                the source only owes reserve for its current owners.
+        // - unsponsored: reserveToAdd — source owes reserve including the new
+        //                increment, which Bytecode can make larger than one unit.
         auto const sourceReserve = accountReserve(
-            ctx_.view(), sle, j_, {.ownerCountDelta = getTxReserveSponsorID(ctx_.tx) ? 0 : 1});
+            ctx_.view(),
+            sle,
+            j_,
+            {.ownerCountDelta = getTxReserveSponsorID(ctx_.tx) ? 0 : reserveToAdd});
         if (balance - STAmount(amount).xrp() < sourceReserve)
             return tecUNFUNDED;
     }
@@ -289,6 +366,8 @@ EscrowCreate::doApply()
     (*escrow)[~sfCancelAfter] = ctx_.tx[~sfCancelAfter];
     (*escrow)[~sfFinishAfter] = ctx_.tx[~sfFinishAfter];
     (*escrow)[~sfDestinationTag] = ctx_.tx[~sfDestinationTag];
+    (*escrow)[~sfBytecode] = ctx_.tx[~sfBytecode];
+    (*escrow)[~sfData] = ctx_.tx[~sfData];
 
     if (ctx_.view().rules().enabled(fixIncludeKeyletFields))
     {
@@ -356,7 +435,7 @@ EscrowCreate::doApply()
     }
 
     // increment owner count
-    increaseOwnerCount(ctx_.getApplyViewContext(), sle, 1, ctx_.journal);
+    increaseOwnerCount(ctx_.getApplyViewContext(), sle, reserveToAdd, ctx_.journal);
     addSponsorToLedgerEntry(ctx_.getApplyViewContext(), escrow.mutableRawSle());
     ctx_.view().update(sle);
     return tesSUCCESS;

src/libxrpl/tx/transactors/escrow/EscrowFinish.cpp

@@ -16,6 +16,7 @@
 #include <xrpl/protocol/AccountID.h>
 #include <xrpl/protocol/Concepts.h>
 #include <xrpl/protocol/Feature.h>
+#include <xrpl/protocol/Fees.h>
 #include <xrpl/protocol/Indexes.h>
 #include <xrpl/protocol/Rate.h>
 #include <xrpl/protocol/SField.h>
@@ -27,6 +28,8 @@
 #include <xrpl/protocol/XRPAmount.h>
 #include <xrpl/tx/Transactor.h>
 
+#include <cstdint>
+#include <optional>
 #include <system_error>
 #include <variant>
 
@@ -79,7 +82,24 @@ EscrowFinish::preflight(PreflightContext const& ctx)
     // If you specify a condition, then you must also specify
     // a fulfillment.
     if (static_cast<bool>(cb) != static_cast<bool>(fb))
+    {
+        JLOG(ctx.j.debug()) << "Condition != Fulfillment";
         return temMALFORMED;
+    }
+
+    if (auto const allowance = ctx.tx[~sfGas]; allowance)
+    {
+        // Protocol ceiling only; `preflight` has no view.
+        if (*allowance == 0)
+        {
+            return temBAD_LIMIT;
+        }
+        if (*allowance > kMaxGasLimit)
+        {
+            JLOG(ctx.j.debug()) << "Gas too large: " << *allowance;
+            return temBAD_LIMIT;
+        }
+    }
 
     return tesSUCCESS;
 }
@@ -148,7 +168,15 @@ EscrowFinish::calculateBaseFee(ReadView const& view, STTx const& tx)
     {
         extraFee += view.fees().base * (32 + (fb->size() / 16));
     }
-
+    if (auto const allowance = tx[~sfGas]; allowance)
+    {
+        // The extra fee is the allowance in drops, rounded up to the nearest
+        // whole drop. Widen before multiplying: both factors are 32-bit.
+        std::uint64_t const allowanceFee =
+            ((std::uint64_t{*allowance} * view.fees().gasPrice) + microDropsPerDrop - 1) /
+            microDropsPerDrop;
+        extraFee += allowanceFee;
+    }
     return Transactor::calculateBaseFee(view, tx) + extraFee;
 }
 
@@ -162,25 +190,66 @@ EscrowFinish::preclaim(PreclaimContext const& ctx)
             return err;
     }
 
-    if (ctx.view.rules().enabled(featureTokenEscrow))
+    if (ctx.view.rules().enabled(featureTokenEscrow) ||
+        ctx.view.rules().enabled(featureSmartEscrow))
     {
+        // this check is done in doApply before this amendment is enabled
         auto const seqProxy = SeqProxy::rawSequence(ctx.tx[sfOfferSequence]);
         EscrowEntryR const escrow(ctx.tx[sfOwner], seqProxy, ctx.view);
         if (!escrow)
             return tecNO_TARGET;
 
-        AccountID const dest = (*escrow)[sfDestination];
-        STAmount const amount = (*escrow)[sfAmount];
-
-        if (!isXRP(amount))
+        if (ctx.view.rules().enabled(featureSmartEscrow))
         {
-            if (auto const ret = std::visit(
-                    [&]<typename T>(T const&) {
-                        return escrowUnlockPreclaimHelper<T>(ctx.view, dest, amount);
-                    },
-                    amount.asset().value());
-                !isTesSuccess(ret))
-                return ret;
+            if (escrow->isFieldPresent(sfBytecode))
+            {
+                if (!ctx.tx.isFieldPresent(sfGas))
+                {
+                    JLOG(ctx.j.debug()) << "Bytecode requires Gas";
+                    return tefBYTECODE_NOT_INCLUDED;
+                }
+
+                // The limits are voted, so they can change between ledgers.
+                // A `tef`, unlike a `tem`, does not mark the transaction bad
+                // for the hold time.
+                auto const& fees = ctx.view.fees();
+                if (isBytecodeExecutionDisabled(fees))
+                {
+                    JLOG(ctx.j.debug()) << "WASM runtime deactivated by fee voting";
+                    return tefTEMP_DISABLED;
+                }
+
+                if (ctx.tx[sfGas] > fees.gasLimit)
+                {
+                    JLOG(ctx.j.debug()) << "Gas over voted limit: " << ctx.tx[sfGas];
+                    return tefEXCEEDS_LIMIT;
+                }
+            }
+            else
+            {
+                if (ctx.tx.isFieldPresent(sfGas))
+                {
+                    JLOG(ctx.j.debug()) << "Bytecode not present, "
+                                           "Gas present";
+                    return tefNO_BYTECODE;
+                }
+            }
+        }
+        if (ctx.view.rules().enabled(featureTokenEscrow))
+        {
+            AccountID const dest = (*escrow)[sfDestination];
+            STAmount const amount = (*escrow)[sfAmount];
+
+            if (!isXRP(amount))
+            {
+                if (auto const ret = std::visit(
+                        [&]<typename T>(T const&) {
+                            return escrowUnlockPreclaimHelper<T>(ctx.view, dest, amount);
+                        },
+                        amount.asset().value());
+                    !isTesSuccess(ret))
+                    return ret;
+            }
         }
     }
     return tesSUCCESS;
@@ -193,7 +262,8 @@ EscrowFinish::doApply()
     EscrowEntryW escrow(ctx_.tx[sfOwner], seqProxy, ctx_.view(), j_);
     if (!escrow)
     {
-        if (ctx_.view().rules().enabled(featureTokenEscrow))
+        if (ctx_.view().rules().enabled(featureTokenEscrow) ||
+            ctx_.view().rules().enabled(featureSmartEscrow))
             return tecINTERNAL;  // LCOV_EXCL_LINE
 
         return tecNO_TARGET;
@@ -211,6 +281,20 @@ EscrowFinish::doApply()
     if ((*escrow)[~sfCancelAfter] && after(now, (*escrow)[sfCancelAfter]))
         return tecNO_PERMISSION;
 
+    AccountID const destID = (*escrow)[sfDestination];
+    auto const sled = ctx_.view().peek(keylet::account(destID));
+    if (ctx_.view().rules().enabled(featureSmartEscrow))
+    {
+        // NOTE: Escrow payments cannot be used to fund accounts.
+        if (!sled)
+            return tecNO_DST;
+
+        if (auto err =
+                verifyDepositPreauth(ctx_.tx, ctx_.view(), accountID_, destID, sled, ctx_.journal);
+            !isTesSuccess(err))
+            return err;
+    }
+
     // Check cryptocondition fulfillment
     {
         auto const id = ctx_.tx.getTransactionID();
@@ -264,16 +348,33 @@ EscrowFinish::doApply()
             return tecCRYPTOCONDITION_ERROR;
     }
 
-    // NOTE: Escrow payments cannot be used to fund accounts.
-    AccountID const destID = (*escrow)[sfDestination];
-    auto const sled = ctx_.view().peek(keylet::account(destID));
-    if (!sled)
-        return tecNO_DST;
+    if (!ctx_.view().rules().enabled(featureSmartEscrow))
+    {
+        // NOTE: Escrow payments cannot be used to fund accounts.
+        if (!sled)
+            return tecNO_DST;
 
-    if (auto err =
-            verifyDepositPreauth(ctx_.tx, ctx_.view(), accountID_, destID, sled, ctx_.journal);
-        !isTesSuccess(err))
-        return err;
+        if (auto err =
+                verifyDepositPreauth(ctx_.tx, ctx_.view(), accountID_, destID, sled, ctx_.journal);
+            !isTesSuccess(err))
+            return err;
+    }
+
+    // Execute custom release function
+    if ((*escrow)[~sfBytecode])
+    {
+        // TODO(SmartEscrow): run the escrow's contract here once the WASM
+        // engine lands. That change also brings with it the reporting the run
+        // produces - the gas it consumed and the code it returned, in the
+        // transaction metadata - and the tecBYTECODE_REJECTED result that lets
+        // a rejected escrow survive with the data the contract wrote.
+        //
+        // Until then an escrow carrying bytecode can be created, funded and
+        // cancelled, but not finished. Reachable only under featureSmartEscrow,
+        // which is Supported::No.
+        JLOG(j_.debug()) << "EscrowFinish: no WASM engine to run the escrow's bytecode";
+        return tecFAILED_PROCESSING;
+    }
 
     AccountID const account = (*escrow)[sfAccount];
 
@@ -301,13 +402,18 @@ EscrowFinish::doApply()
         }
     }
 
+    auto const reserveToSubtract = calculateAdditionalReserve((*escrow)[~sfBytecode]);
+
     // Delivery can auto-create the destination's holding; the removed escrow
     // must not be counted against its reserve. The two share a reserve payer
     // for a self-escrow, or when one sponsor covers both.
     bool const recycleReserve =
         ctx_.view().rules().enabled(featureSponsor) || ctx_.view().rules().enabled(fixCleanup3_4_0);
     if (recycleReserve)
-        decreaseOwnerCountForObject(ctx_.view(), account, escrow.mutableRawSle(), 1, ctx_.journal);
+    {
+        decreaseOwnerCountForObject(
+            ctx_.view(), account, escrow.mutableRawSle(), reserveToSubtract, ctx_.journal);
+    }
 
     STAmount const amount = escrow->getFieldAmount(sfAmount);
     // Transfer amount to destination
@@ -359,7 +465,10 @@ EscrowFinish::doApply()
     ctx_.view().update(sled);
 
     if (!recycleReserve)
-        decreaseOwnerCountForObject(ctx_.view(), account, escrow.mutableRawSle(), 1, ctx_.journal);
+    {
+        decreaseOwnerCountForObject(
+            ctx_.view(), account, escrow.mutableRawSle(), reserveToSubtract, ctx_.journal);
+    }
 
     // Remove escrow from ledger
     escrow.erase();

src/libxrpl/tx/transactors/proposal/TransactionProposalCancel.cpp

@@ -37,7 +37,7 @@ TransactionProposalCancel::preclaim(PreclaimContext const& ctx)
 
     // Never read the zero keylet. Preflight already rejected a zero
     // ProposalID, and no real proposal can have one (every ProposalID is a
-    // hash), so reaching here with zero is an internal error. (and a mathematical rarity. )
+    // hash), so reaching here with zero is an internal error (and a mathematical rarity).
     if (proposalID == beast::kZero)
         return tefINTERNAL;  // LCOV_EXCL_LINE
 

src/test/app/AccountDelete_test.cpp

@@ -32,6 +32,7 @@
 #include <xrpl/json/json_value.h>
 #include <xrpl/json/to_string.h>
 #include <xrpl/ledger/ReadView.h>
+#include <xrpl/protocol/ErrorCodes.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/Indexes.h>
 #include <xrpl/protocol/Issue.h>
@@ -894,8 +895,9 @@ public:
                 auto const jNoCred = credentials::ledgerEntry(env, becky, carol, credType);
                 BEAST_EXPECT(
                     jNoCred.isObject() && jNoCred.isMember(jss::result) &&
-                    jNoCred[jss::result].isMember(jss::error) &&
-                    jNoCred[jss::result][jss::error] == "entryNotFound");
+                    jNoCred[jss::result][jss::error] == "entryNotFound" &&
+                    jNoCred[jss::result][jss::error_code] == RpcEntryNotFound &&
+                    jNoCred[jss::result][jss::error_message] == "Entry not found.");
             }
 
             testcase("Credentials that aren't required");
@@ -918,8 +920,9 @@ public:
 
                 BEAST_EXPECT(
                     jNoCred.isObject() && jNoCred.isMember(jss::result) &&
-                    jNoCred[jss::result].isMember(jss::error) &&
-                    jNoCred[jss::result][jss::error] == "entryNotFound");
+                    jNoCred[jss::result][jss::error] == "entryNotFound" &&
+                    jNoCred[jss::result][jss::error_code] == RpcEntryNotFound &&
+                    jNoCred[jss::result][jss::error_message] == "Entry not found.");
             }
 
             {
@@ -957,8 +960,9 @@ public:
 
                 BEAST_EXPECT(
                     jNoCred.isObject() && jNoCred.isMember(jss::result) &&
-                    jNoCred[jss::result].isMember(jss::error) &&
-                    jNoCred[jss::result][jss::error] == "entryNotFound");
+                    jNoCred[jss::result][jss::error] == "entryNotFound" &&
+                    jNoCred[jss::result][jss::error_code] == RpcEntryNotFound &&
+                    jNoCred[jss::result][jss::error_message] == "Entry not found.");
             }
 
             testcase("Expired credentials");
@@ -994,8 +998,9 @@ public:
                     auto jv = credentials::ledgerEntry(env, john, carol, credType);
                     BEAST_EXPECT(
                         jv.isObject() && jv.isMember(jss::result) &&
-                        jv[jss::result].isMember(jss::error) &&
-                        jv[jss::result][jss::error] == "entryNotFound");
+                        jv[jss::result][jss::error] == "entryNotFound" &&
+                        jv[jss::result][jss::error_code] == RpcEntryNotFound &&
+                        jv[jss::result][jss::error_message] == "Entry not found.");
                 }
             }
         }
@@ -1079,8 +1084,9 @@ public:
                 auto const jv = credentials::ledgerEntry(env, becky, carol, credType);
                 BEAST_EXPECT(
                     jv.isObject() && jv.isMember(jss::result) &&
-                    jv[jss::result].isMember(jss::error) &&
-                    jv[jss::result][jss::error] == "entryNotFound");
+                    jv[jss::result][jss::error] == "entryNotFound" &&
+                    jv[jss::result][jss::error_code] == RpcEntryNotFound &&
+                    jv[jss::result][jss::error_message] == "Entry not found.");
             }
         }
 
@@ -1121,8 +1127,9 @@ public:
                 auto const jv = credentials::ledgerEntry(env, becky, carol, credType);
                 BEAST_EXPECT(
                     jv.isObject() && jv.isMember(jss::result) &&
-                    jv[jss::result].isMember(jss::error) &&
-                    jv[jss::result][jss::error] == "entryNotFound");
+                    jv[jss::result][jss::error] == "entryNotFound" &&
+                    jv[jss::result][jss::error_code] == RpcEntryNotFound &&
+                    jv[jss::result][jss::error_message] == "Entry not found.");
             }
         }
     }

src/test/app/Batch_test.cpp

@@ -43,6 +43,7 @@
 #include <xrpl/ledger/OpenView.h>
 #include <xrpl/protocol/AccountID.h>
 #include <xrpl/protocol/Batch.h>
+#include <xrpl/protocol/ErrorCodes.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/Indexes.h>
 #include <xrpl/protocol/Issue.h>
@@ -2800,6 +2801,7 @@ class Batch_test : public beast::unit_test::Suite
             auto const jrr = env.rpc("submit", strHex(slice))[jss::result];
             expect(
                 jrr[jss::status] == "error" && jrr[jss::error] == "invalidTransaction" &&
+                    !jrr.isMember(jss::error_code) && jrr[jss::error_message].isNull() &&
                     jrr[jss::error_exception] ==
                         "fails local checks: Batch inner transactions are never "
                         "considered validly signed.",
@@ -5407,7 +5409,10 @@ class Batch_test : public beast::unit_test::Suite
 
             // The delegated payment never applied.
             BEAST_EXPECT(env.balance(mallory) == preMallory);
-            BEAST_EXPECT(env.rpc("tx", txIDs[1])[jss::result][jss::error] == "txnNotFound");
+            auto const txResult = env.rpc("tx", txIDs[1])[jss::result];
+            BEAST_EXPECT(txResult[jss::error] == "txnNotFound");
+            BEAST_EXPECT(txResult[jss::error_code] == RpcTxnNotFound);
+            BEAST_EXPECT(txResult[jss::error_message] == "Transaction not found.");
         }
     }
 
@@ -5818,7 +5823,10 @@ class Batch_test : public beast::unit_test::Suite
             validateClosedLedger(env, testCases);
 
             // verify jv2 is not present in the closed ledger.
-            BEAST_EXPECT(env.rpc("tx", txIDs[1])[jss::result][jss::error] == "txnNotFound");
+            auto const txResult = env.rpc("tx", txIDs[1])[jss::result];
+            BEAST_EXPECT(txResult[jss::error] == "txnNotFound");
+            BEAST_EXPECT(txResult[jss::error_code] == RpcTxnNotFound);
+            BEAST_EXPECT(txResult[jss::error_message] == "Transaction not found.");
         }
     }
 

src/test/app/Clawback_test.cpp

@@ -1,4 +1,5 @@
 #include <test/jtx/Account.h>
+#include <test/jtx/CaptureLogs.h>
 #include <test/jtx/Env.h>
 #include <test/jtx/TestHelpers.h>
 #include <test/jtx/amount.h>
@@ -14,13 +15,17 @@
 #include <xrpl/beast/unit_test/suite.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/Indexes.h>
+#include <xrpl/protocol/Issue.h>
 #include <xrpl/protocol/LedgerFormats.h>
 #include <xrpl/protocol/SField.h>
+#include <xrpl/protocol/STAmount.h>
 #include <xrpl/protocol/TER.h>
 #include <xrpl/protocol/TxFlags.h>
 #include <xrpl/protocol/UintTypes.h>
 
+#include <array>
 #include <cstdint>
+#include <memory>
 #include <stdexcept>
 #include <string>
 
@@ -803,6 +808,108 @@ class Clawback_test : public beast::unit_test::Suite
         BEAST_EXPECT(ownerCount(env, bob) == 0);
     }
 
+    void
+    testSubResolutionAmount(FeatureBitset features)
+    {
+        testcase("Sub-resolution amount");
+        using namespace test::jtx;
+
+        // IOU balances keep 16 significant digits. When alice claws back an
+        // amount much smaller than bob's balance, the balance changes by the
+        // rounded amount, which can be zero, less, or more than requested. The
+        // clawback invariant must accept that instead of failing the
+        // transaction under MPTokensV2 or logging a failure without it.
+        Account const alice{"alice"};
+        Account const bob{"bob"};
+
+        struct Case
+        {
+            std::uint64_t balanceMantissa;
+            int balanceExponent;
+            std::uint64_t clawMantissa;
+            int clawExponent;
+            std::uint64_t afterMantissa;
+            int afterExponent;
+        };
+        std::array const cases{
+            // 1e7 - 1e-10 rounds back to 1e7
+            Case{
+                .balanceMantissa = 10'000'000,
+                .balanceExponent = 0,
+                .clawMantissa = 1,
+                .clawExponent = -10,
+                .afterMantissa = 10'000'000,
+                .afterExponent = 0,
+            },
+            // 1234567890.123456 - 0.0000005 rounds back to the balance
+            Case{
+                .balanceMantissa = 1'234'567'890'123'456,
+                .balanceExponent = -6,
+                .clawMantissa = 5,
+                .clawExponent = -7,
+                .afterMantissa = 1'234'567'890'123'456,
+                .afterExponent = -6,
+            },
+            // 0.0000014 removes 0.000001
+            Case{
+                .balanceMantissa = 1'234'567'890'123'456,
+                .balanceExponent = -6,
+                .clawMantissa = 14,
+                .clawExponent = -7,
+                .afterMantissa = 1'234'567'890'123'455,
+                .afterExponent = -6,
+            },
+            // 0.0000016 removes 0.000002
+            Case{
+                .balanceMantissa = 1'234'567'890'123'456,
+                .balanceExponent = -6,
+                .clawMantissa = 16,
+                .clawExponent = -7,
+                .afterMantissa = 1'234'567'890'123'454,
+                .afterExponent = -6,
+            },
+        };
+
+        for (auto const feat : {features, features - featureMPTokensV2})
+        {
+            for (auto const& c : cases)
+            {
+                std::string logs;
+                {
+                    Env env(*this, feat, std::make_unique<test::CaptureLogs>(&logs));
+
+                    env.fund(XRP(1000), alice, bob);
+                    env.close();
+
+                    auto const usd = alice["USD"];
+
+                    env(fset(alice, asfAllowTrustLineClawback));
+                    env.close();
+
+                    env.trust(usd(10'000'000'000), bob);
+                    env(pay(
+                        alice, bob, STAmount{usd.issue(), c.balanceMantissa, c.balanceExponent}));
+                    env.close();
+
+                    env(claw(
+                            alice,
+                            STAmount{
+                                Issue{usd.currency, bob.id()}, c.clawMantissa, c.clawExponent}),
+                        Ter(tesSUCCESS));
+                    env.close();
+
+                    BEAST_EXPECT(
+                        env.balance(bob, usd).value() ==
+                        STAmount(usd.issue(), c.afterMantissa, c.afterExponent));
+                }
+                // Without MPTokensV2 a failed invariant only logs and the
+                // transaction still succeeds, so check the logs instead.
+                if (!feat[featureMPTokensV2])
+                    BEAST_EXPECT(!logs.contains("Invariant failed"));
+            }
+        }
+    }
+
     void
     testTickets(FeatureBitset features)
     {
@@ -872,6 +979,7 @@ class Clawback_test : public beast::unit_test::Suite
         testDeleteDefaultLine(features);
         testFrozenLine(features);
         testAmountExceedsAvailable(features);
+        testSubResolutionAmount(features);
         testTickets(features);
     }
 

src/test/app/ConfidentialTransferExtended_test.cpp

@@ -20,6 +20,7 @@
 #include <xrpl/beast/unit_test/suite.h>
 #include <xrpl/json/json_value.h>
 #include <xrpl/protocol/ConfidentialTransfer.h>
+#include <xrpl/protocol/ErrorCodes.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/Indexes.h>
 #include <xrpl/protocol/Protocol.h>
@@ -259,8 +260,9 @@ class ConfidentialTransferExtended_test : public ConfidentialTransferTestBase
 
         auto const credentialDeleted = [&](Env& env, Account const& subject) -> bool {
             auto const credentials = credentials::ledgerEntry(env, subject, dpIssuer, credType);
-            return credentials[jss::result].isMember(jss::error) &&
-                credentials[jss::result][jss::error] == "entryNotFound";
+            return credentials[jss::result][jss::error] == "entryNotFound" &&
+                credentials[jss::result][jss::error_code] == RpcEntryNotFound &&
+                credentials[jss::result][jss::error_message] == "Entry not found.";
         };
 
         // TEST 4: Expired credential with matching depositPreauth entry.

src/test/app/ConfidentialTransfer_test.cpp

@@ -7944,6 +7944,8 @@ class ConfidentialTransfer_test : public ConfidentialTransferTestBase
             // Signature verification fails — rejected before ZKP check
             auto const jr = env.rpc("submit", strHex(tampered.slice()));
             BEAST_EXPECT(jr[jss::result][jss::error] == "invalidTransaction");
+            BEAST_EXPECT(!jr[jss::result].isMember(jss::error_code));
+            BEAST_EXPECT(jr[jss::result][jss::error_message].isNull());
         }
 
         // Variant B: Re-signed with inflated ciphertext.
@@ -8051,6 +8053,8 @@ class ConfidentialTransfer_test : public ConfidentialTransferTestBase
 
             auto const jr = env.rpc("submit", strHex(tampered.slice()));
             BEAST_EXPECT(jr[jss::result][jss::error] == "invalidTransaction");
+            BEAST_EXPECT(!jr[jss::result].isMember(jss::error_code));
+            BEAST_EXPECT(jr[jss::result][jss::error_message].isNull());
         }
 
         // Variant B: Re-signed with all negated ciphertexts.
@@ -8154,6 +8158,8 @@ class ConfidentialTransfer_test : public ConfidentialTransferTestBase
 
             auto const jr = env.rpc("submit", strHex(tampered.slice()));
             BEAST_EXPECT(jr[jss::result][jss::error] == "invalidTransaction");
+            BEAST_EXPECT(!jr[jss::result].isMember(jss::error_code));
+            BEAST_EXPECT(jr[jss::result][jss::error_message].isNull());
         }
 
         // Variant B: Re-signed with combined ciphertext.
@@ -8278,6 +8284,8 @@ class ConfidentialTransfer_test : public ConfidentialTransferTestBase
             // Signature verification fails
             auto const jr = env.rpc("submit", strHex(tampered.slice()));
             BEAST_EXPECT(jr[jss::result][jss::error] == "invalidTransaction");
+            BEAST_EXPECT(!jr[jss::result].isMember(jss::error_code));
+            BEAST_EXPECT(jr[jss::result][jss::error_message].isNull());
         }
 
         // Variant B: Re-signed C1 substitution.
@@ -8368,6 +8376,8 @@ class ConfidentialTransfer_test : public ConfidentialTransferTestBase
             // signed — transaction rejected before ZKP verification.
             auto const jr = env.rpc("submit", strHex(tampered.slice()));
             BEAST_EXPECT(jr[jss::result][jss::error] == "invalidTransaction");
+            BEAST_EXPECT(!jr[jss::result].isMember(jss::error_code));
+            BEAST_EXPECT(jr[jss::result][jss::error_message].isNull());
         }
 
         // -----------------------------------------------------------------

src/test/app/Credentials_test.cpp

@@ -23,6 +23,7 @@
 #include <xrpl/ledger/ApplyViewImpl.h>
 #include <xrpl/ledger/helpers/CredentialHelpers.h>
 #include <xrpl/protocol/AccountID.h>
+#include <xrpl/protocol/ErrorCodes.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/Indexes.h>
 #include <xrpl/protocol/Issue.h>
@@ -124,8 +125,9 @@ struct Credentials_test : public beast::unit_test::Suite
                 auto const jle = credentials::ledgerEntry(env, subject, issuer, credType);
                 BEAST_EXPECT(
                     jle.isObject() && jle.isMember(jss::result) &&
-                    jle[jss::result].isMember(jss::error) &&
-                    jle[jss::result][jss::error] == "entryNotFound");
+                    jle[jss::result][jss::error] == "entryNotFound" &&
+                    jle[jss::result][jss::error_code] == RpcEntryNotFound &&
+                    jle[jss::result][jss::error_message] == "Entry not found.");
             }
         }
 
@@ -173,8 +175,9 @@ struct Credentials_test : public beast::unit_test::Suite
                 auto const jle = credentials::ledgerEntry(env, issuer, issuer, credType);
                 BEAST_EXPECT(
                     jle.isObject() && jle.isMember(jss::result) &&
-                    jle[jss::result].isMember(jss::error) &&
-                    jle[jss::result][jss::error] == "entryNotFound");
+                    jle[jss::result][jss::error] == "entryNotFound" &&
+                    jle[jss::result][jss::error_code] == RpcEntryNotFound &&
+                    jle[jss::result][jss::error_message] == "Entry not found.");
             }
         }
     }
@@ -222,8 +225,9 @@ struct Credentials_test : public beast::unit_test::Suite
                 auto const jle = credentials::ledgerEntry(env, subject, issuer, credType);
                 BEAST_EXPECT(
                     jle.isObject() && jle.isMember(jss::result) &&
-                    jle[jss::result].isMember(jss::error) &&
-                    jle[jss::result][jss::error] == "entryNotFound");
+                    jle[jss::result][jss::error] == "entryNotFound" &&
+                    jle[jss::result][jss::error_code] == RpcEntryNotFound &&
+                    jle[jss::result][jss::error_message] == "Entry not found.");
             }
 
             // resurrection
@@ -259,8 +263,9 @@ struct Credentials_test : public beast::unit_test::Suite
                 auto const jle = credentials::ledgerEntry(env, subject, issuer, credType);
                 BEAST_EXPECT(
                     jle.isObject() && jle.isMember(jss::result) &&
-                    jle[jss::result].isMember(jss::error) &&
-                    jle[jss::result][jss::error] == "entryNotFound");
+                    jle[jss::result][jss::error] == "entryNotFound" &&
+                    jle[jss::result][jss::error_code] == RpcEntryNotFound &&
+                    jle[jss::result][jss::error_message] == "Entry not found.");
             }
 
             // resurrection
@@ -294,8 +299,9 @@ struct Credentials_test : public beast::unit_test::Suite
                 auto const jle = credentials::ledgerEntry(env, subject, issuer, credType);
                 BEAST_EXPECT(
                     jle.isObject() && jle.isMember(jss::result) &&
-                    jle[jss::result].isMember(jss::error) &&
-                    jle[jss::result][jss::error] == "entryNotFound");
+                    jle[jss::result][jss::error] == "entryNotFound" &&
+                    jle[jss::result][jss::error_code] == RpcEntryNotFound &&
+                    jle[jss::result][jss::error_message] == "Entry not found.");
             }
 
             // resurrection
@@ -331,8 +337,9 @@ struct Credentials_test : public beast::unit_test::Suite
                 auto const jle = credentials::ledgerEntry(env, subject, issuer, credType);
                 BEAST_EXPECT(
                     jle.isObject() && jle.isMember(jss::result) &&
-                    jle[jss::result].isMember(jss::error) &&
-                    jle[jss::result][jss::error] == "entryNotFound");
+                    jle[jss::result][jss::error] == "entryNotFound" &&
+                    jle[jss::result][jss::error_code] == RpcEntryNotFound &&
+                    jle[jss::result][jss::error_message] == "Entry not found.");
             }
 
             // resurrection
@@ -368,8 +375,9 @@ struct Credentials_test : public beast::unit_test::Suite
                 auto const jle = credentials::ledgerEntry(env, subject, issuer, credType);
                 BEAST_EXPECT(
                     jle.isObject() && jle.isMember(jss::result) &&
-                    jle[jss::result].isMember(jss::error) &&
-                    jle[jss::result][jss::error] == "entryNotFound");
+                    jle[jss::result][jss::error] == "entryNotFound" &&
+                    jle[jss::result][jss::error_code] == RpcEntryNotFound &&
+                    jle[jss::result][jss::error_message] == "Entry not found.");
             }
         }
 
@@ -390,8 +398,9 @@ struct Credentials_test : public beast::unit_test::Suite
                 auto const jle = credentials::ledgerEntry(env, subject, issuer, credType);
                 BEAST_EXPECT(
                     jle.isObject() && jle.isMember(jss::result) &&
-                    jle[jss::result].isMember(jss::error) &&
-                    jle[jss::result][jss::error] == "entryNotFound");
+                    jle[jss::result][jss::error] == "entryNotFound" &&
+                    jle[jss::result][jss::error_code] == RpcEntryNotFound &&
+                    jle[jss::result][jss::error_message] == "Entry not found.");
             }
         }
 
@@ -410,8 +419,9 @@ struct Credentials_test : public beast::unit_test::Suite
                 auto const jle = credentials::ledgerEntry(env, subject, issuer, credType);
                 BEAST_EXPECT(
                     jle.isObject() && jle.isMember(jss::result) &&
-                    jle[jss::result].isMember(jss::error) &&
-                    jle[jss::result][jss::error] == "entryNotFound");
+                    jle[jss::result][jss::error] == "entryNotFound" &&
+                    jle[jss::result][jss::error_code] == RpcEntryNotFound &&
+                    jle[jss::result][jss::error_message] == "Entry not found.");
             }
         }
     }
@@ -744,8 +754,9 @@ struct Credentials_test : public beast::unit_test::Suite
                 auto const jDelCred = credentials::ledgerEntry(env, subject, issuer, credType2);
                 BEAST_EXPECT(
                     jDelCred.isObject() && jDelCred.isMember(jss::result) &&
-                    jDelCred[jss::result].isMember(jss::error) &&
-                    jDelCred[jss::result][jss::error] == "entryNotFound");
+                    jDelCred[jss::result][jss::error] == "entryNotFound" &&
+                    jDelCred[jss::result][jss::error_code] == RpcEntryNotFound &&
+                    jDelCred[jss::result][jss::error_message] == "Entry not found.");
 
                 BEAST_EXPECT(ownerCount(env, issuer) == 0);
                 BEAST_EXPECT(ownerCount(env, subject) == 1);
@@ -781,8 +792,9 @@ struct Credentials_test : public beast::unit_test::Suite
                 auto const jDelCred = credentials::ledgerEntry(env, subject, issuer, credType);
                 BEAST_EXPECT(
                     jDelCred.isObject() && jDelCred.isMember(jss::result) &&
-                    jDelCred[jss::result].isMember(jss::error) &&
-                    jDelCred[jss::result][jss::error] == "entryNotFound");
+                    jDelCred[jss::result][jss::error] == "entryNotFound" &&
+                    jDelCred[jss::result][jss::error_code] == RpcEntryNotFound &&
+                    jDelCred[jss::result][jss::error_message] == "Entry not found.");
             }
         }
     }

src/test/app/Delegate_test.cpp

@@ -38,6 +38,7 @@
 #include <xrpl/json/to_string.h>
 #include <xrpl/ledger/Dir.h>
 #include <xrpl/ledger/helpers/DelegateHelpers.h>
+#include <xrpl/protocol/ErrorCodes.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/Indexes.h>
 #include <xrpl/protocol/Issue.h>
@@ -159,6 +160,8 @@ class Delegate_test : public beast::unit_test::Suite
         env.close();
         auto const jle = delegate::entry(env, gw, alice);
         BEAST_EXPECT(jle[jss::result][jss::error] == "entryNotFound");
+        BEAST_EXPECT(jle[jss::result][jss::error_code] == RpcEntryNotFound);
+        BEAST_EXPECT(jle[jss::result][jss::error_message] == "Entry not found.");
 
         // alice can delegate permissions to gw as well
         env(delegate::set(alice, gw, permissions));
@@ -167,6 +170,8 @@ class Delegate_test : public beast::unit_test::Suite
         auto const response = delegate::entry(env, gw, alice);
         // alice has not been granted any permissions by gw
         BEAST_EXPECT(response[jss::result][jss::error] == "entryNotFound");
+        BEAST_EXPECT(response[jss::result][jss::error_code] == RpcEntryNotFound);
+        BEAST_EXPECT(response[jss::result][jss::error_message] == "Entry not found.");
     }
 
     void
@@ -2780,9 +2785,11 @@ class Delegate_test : public beast::unit_test::Suite
             jv[jss::secret] = bob.name();
             auto jrr = env.rpc("json", "sign_for", to_string(jv))[jss::result];
             BEAST_EXPECT(jrr[jss::status] == "error");
+            BEAST_EXPECT(jrr[jss::error] == "invalidParams");
+            BEAST_EXPECT(jrr[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(
-                jrr[jss::error_message].asString().contains(
-                    "A Signer may not be the transaction's Account"));
+                jrr[jss::error_message] ==
+                "A Signer may not be the transaction's Account (" + bob.human() + ").");
         }
     }
 

src/test/app/DepositAuth_test.cpp

@@ -28,6 +28,7 @@
 #include <xrpl/json/json_value.h>
 #include <xrpl/json/to_string.h>
 #include <xrpl/protocol/AccountID.h>
+#include <xrpl/protocol/ErrorCodes.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/Issue.h>
 #include <xrpl/protocol/LedgerFormats.h>
@@ -1143,8 +1144,9 @@ struct DepositPreauth_test : public beast::unit_test::Suite
                     ledgerEntryDepositPreauth(env, bob, {{.issuer = issuer, .credType = credType}});
                 BEAST_EXPECT(
                     jDP.isObject() && jDP.isMember(jss::result) &&
-                    jDP[jss::result].isMember(jss::error) &&
-                    jDP[jss::result][jss::error] == "entryNotFound");
+                    jDP[jss::result][jss::error] == "entryNotFound" &&
+                    jDP[jss::result][jss::error_code] == RpcEntryNotFound &&
+                    jDP[jss::result][jss::error_message] == "Entry not found.");
             }
         }
     }
@@ -1232,8 +1234,9 @@ struct DepositPreauth_test : public beast::unit_test::Suite
                     auto const jDelCred = credentials::ledgerEntry(env, alice, issuer, credType);
                     BEAST_EXPECT(
                         jDelCred.isObject() && jDelCred.isMember(jss::result) &&
-                        jDelCred[jss::result].isMember(jss::error) &&
-                        jDelCred[jss::result][jss::error] == "entryNotFound");
+                        jDelCred[jss::result][jss::error] == "entryNotFound" &&
+                        jDelCred[jss::result][jss::error_code] == RpcEntryNotFound &&
+                        jDelCred[jss::result][jss::error_message] == "Entry not found.");
                 }
 
                 {
@@ -1283,8 +1286,9 @@ struct DepositPreauth_test : public beast::unit_test::Suite
                 auto const jDelCred = credentials::ledgerEntry(env, gw, issuer, credType);
                 BEAST_EXPECT(
                     jDelCred.isObject() && jDelCred.isMember(jss::result) &&
-                    jDelCred[jss::result].isMember(jss::error) &&
-                    jDelCred[jss::result][jss::error] == "entryNotFound");
+                    jDelCred[jss::result][jss::error] == "entryNotFound" &&
+                    jDelCred[jss::result][jss::error_code] == RpcEntryNotFound &&
+                    jDelCred[jss::result][jss::error_message] == "Entry not found.");
 
                 BEAST_EXPECT(ownerCount(env, issuer) == 0);
                 BEAST_EXPECT(ownerCount(env, gw) == 0);
@@ -1358,8 +1362,9 @@ struct DepositPreauth_test : public beast::unit_test::Suite
             auto const jDelCred = credentials::ledgerEntry(env, zelda, issuer, credType);
             BEAST_EXPECT(
                 jDelCred.isObject() && jDelCred.isMember(jss::result) &&
-                jDelCred[jss::result].isMember(jss::error) &&
-                jDelCred[jss::result][jss::error] == "entryNotFound");
+                jDelCred[jss::result][jss::error] == "entryNotFound" &&
+                jDelCred[jss::result][jss::error_code] == RpcEntryNotFound &&
+                jDelCred[jss::result][jss::error_message] == "Entry not found.");
         }
     }
 

src/test/app/EscrowSmart_test.cpp

@@ -0,0 +1,787 @@
+#include <test/jtx/Account.h>
+#include <test/jtx/Env.h>
+#include <test/jtx/TestHelpers.h>
+#include <test/jtx/amount.h>
+#include <test/jtx/envconfig.h>
+#include <test/jtx/escrow.h>
+#include <test/jtx/fee.h>
+#include <test/jtx/ter.h>
+
+#include <xrpld/core/Config.h>
+
+#include <xrpl/basics/strHex.h>
+#include <xrpl/beast/unit_test/suite.h>
+#include <xrpl/config/Constants.h>
+#include <xrpl/core/StartUpType.h>
+#include <xrpl/protocol/Feature.h>
+#include <xrpl/protocol/Fees.h>
+#include <xrpl/protocol/Indexes.h>
+#include <xrpl/protocol/Protocol.h>
+#include <xrpl/protocol/SField.h>
+#include <xrpl/protocol/SeqProxy.h>
+#include <xrpl/protocol/TER.h>
+#include <xrpl/protocol/XRPAmount.h>
+
+#include <cstddef>
+#include <cstdint>
+#include <memory>
+#include <string>
+
+namespace xrpl::test {
+
+/**
+ * Smart Escrow's `Bytecode`, `Data` and `Gas` fields.
+ *
+ *  The WASM engine that runs an escrow's bytecode is not in this build, so the
+ *  `Bytecode` field is opaque here: `EscrowCreate` weighs its size and nothing
+ *  reads it, and `EscrowFinish` has nothing to run it with. Everything around
+ *  the run is testable, and is tested below - the preflight and preclaim rules,
+ *  the fee the bytecode costs, the owner reserve it occupies, and the refund of
+ *  that reserve.
+ *
+ *  What waits on the engine: a successful finish, tecBYTECODE_REJECTED, the
+ *  gas and return code the run reports in the transaction metadata, and the
+ *  `Data` a rejected contract leaves behind.
+ */
+struct EscrowSmart_test : public beast::unit_test::Suite
+{
+    // A blob of `bytes` bytes, as hex. Opens with the WASM preamble - "\0asm"
+    // and version 1 - so a reader can see what the field is meant to carry,
+    // but nothing in this build parses it.
+    static std::string
+    bytecodeOfSize(std::size_t bytes)
+    {
+        static std::string const kPreamble = "0061736D01000000";
+        std::string hex = kPreamble;
+        hex.append((bytes * 2) - kPreamble.size(), 'A');
+        return hex;
+    }
+
+    // What EscrowCreate charges for `bytecodeHex`: ten base fees, plus five
+    // drops per byte.
+    static XRPAmount
+    createFeeFor(jtx::Env const& env, std::string const& bytecodeHex)
+    {
+        return env.current()->fees().base * 10 + bytecodeHex.size() / 2 * 5;
+    }
+
+    // A validator's config that votes for `value` on the fee setting `key`.
+    static std::unique_ptr<Config>
+    votingFor(std::string const& key, std::uint32_t value)
+    {
+        auto cfg = jtx::envconfig(jtx::validator, "");
+        cfg->section(Sections::kVoting).set(key, std::to_string(value));
+        return cfg;
+    }
+
+    // Close past the flag ledger, so the vote lands in FeeSettings.
+    static void
+    closePastFlagLedger(jtx::Env& env)
+    {
+        for (auto i = env.current()->seq(); i <= 257; ++i)
+            env.close();
+    }
+
+    // What EscrowFinish charges for `gas`: the gas cost rounded up to the drop.
+    static XRPAmount
+    finishFeeFor(jtx::Env const& env, std::uint64_t gas)
+    {
+        return env.current()->fees().base +
+            ((gas * env.current()->fees().gasPrice) + microDropsPerDrop - 1) / microDropsPerDrop;
+    }
+
+    void
+    testCreatePreflight(FeatureBitset features)
+    {
+        testcase("EscrowCreate preflight");
+
+        using namespace jtx;
+        using namespace std::chrono;
+
+        Account const alice{"alice"};
+        Account const carol{"carol"};
+
+        auto const bytecode = bytecodeOfSize(64);
+
+        {
+            // featureSmartEscrow disabled
+            Env env(*this, features - featureSmartEscrow);
+            env.fund(XRP(5000), alice, carol);
+            XRPAmount const txnFees = env.current()->fees().base + 1000;
+            auto const escrowCreate = escrow::create(alice, carol, XRP(1000));
+            env(escrowCreate,
+                escrow::Bytecode(bytecode),
+                escrow::kCancelTime(env.now() + 100s),
+                Fee(txnFees),
+                Ter(temDISABLED));
+            env.close();
+
+            env(escrowCreate,
+                escrow::Bytecode(bytecode),
+                escrow::kCancelTime(env.now() + 100s),
+                escrow::Data("00112233"),
+                Fee(txnFees),
+                Ter(temDISABLED));
+            env.close();
+
+            env(escrowCreate,
+                escrow::Data("00112233"),
+                escrow::kFinishTime(env.now() + 100s),
+                Fee(txnFees),
+                Ter(temDISABLED));
+            env.close();
+        }
+
+        {
+            // Bytecode > max length
+            Env env(*this, votingFor(Keys::kBytecodeSizeLimit, 10), features);  // 10 bytes
+            closePastFlagLedger(env);
+            XRPAmount const txnFees = env.current()->fees().base + 1000;
+            env.fund(XRP(5000), alice, carol);
+
+            auto const escrowCreate = escrow::create(alice, carol, XRP(500));
+
+            // 11-byte string
+            std::string const longBytecode = "00112233445566778899AA";
+            env(escrowCreate,
+                escrow::Bytecode(longBytecode),
+                escrow::kCancelTime(env.now() + 100s),
+                Fee(txnFees),
+                Ter(tefEXCEEDS_LIMIT));
+            env.close();
+        }
+
+        {
+            // gas limit set to 0
+            Env env(*this, votingFor(Keys::kGasLimit, 0), features);  // WASM runtime disabled
+            closePastFlagLedger(env);
+            XRPAmount const txnFees = env.current()->fees().base + 1000;
+            env.fund(XRP(5000), alice, carol);
+
+            auto const escrowCreate = escrow::create(alice, carol, XRP(500));
+
+            env(escrowCreate,
+                escrow::Bytecode(bytecode),
+                escrow::kCancelTime(env.now() + 100s),
+                Fee(txnFees),
+                Ter(tefTEMP_DISABLED));
+            env.close();
+        }
+
+        {
+            // size limit set to 0
+            Env env(
+                *this, votingFor(Keys::kBytecodeSizeLimit, 0), features);  // WASM upload disabled
+            closePastFlagLedger(env);
+            XRPAmount const txnFees = env.current()->fees().base + 1000;
+            env.fund(XRP(5000), alice, carol);
+
+            auto const escrowCreate = escrow::create(alice, carol, XRP(500));
+
+            // 1-byte string
+            env(escrowCreate,
+                escrow::Bytecode("AA"),
+                escrow::kCancelTime(env.now() + 100s),
+                Fee(txnFees),
+                Ter(tefTEMP_DISABLED));
+            env.close();
+
+            env(escrowCreate,
+                escrow::Bytecode(bytecode),
+                escrow::kCancelTime(env.now() + 100s),
+                Fee(txnFees),
+                Ter(tefTEMP_DISABLED));
+            env.close();
+        }
+
+        {
+            // Data without Bytecode
+            Env env(*this, features);
+            XRPAmount const txnFees = env.current()->fees().base + 100000;
+            env.fund(XRP(5000), alice, carol);
+
+            auto const escrowCreate = escrow::create(alice, carol, XRP(500));
+
+            std::string const data(4, 'A');
+            env(escrowCreate,
+                escrow::Data(data),
+                escrow::kFinishTime(env.now() + 100s),
+                Fee(txnFees),
+                Ter(temMALFORMED));
+            env.close();
+        }
+
+        {
+            // Data > max length
+            Env env(*this, features);
+            XRPAmount const txnFees = env.current()->fees().base + 100000;
+            env.fund(XRP(5000), alice, carol);
+
+            auto const escrowCreate = escrow::create(alice, carol, XRP(500));
+
+            // string of length (kMaxWasmDataLength + 1) * 2
+            std::string const longData((kMaxWasmDataLength + 1) * 2, 'B');
+            env(escrowCreate,
+                escrow::Data(longData),
+                escrow::Bytecode(bytecode),
+                escrow::kCancelTime(env.now() + 100s),
+                Fee(txnFees),
+                Ter(temMALFORMED));
+            env.close();
+        }
+
+        // Bytecode joins FinishAfter and Condition as a way to say how the
+        // escrow completes, but it always needs a CancelAfter: nothing else
+        // can free the funds if the contract never accepts.
+        Env env(
+            *this,
+            envconfig([](std::unique_ptr<Config> cfg) {
+                cfg->startUp = StartUpType::Fresh;
+                return cfg;
+            }),
+            features);
+        env.fund(XRP(5000), alice, carol);
+
+        auto const escrowCreate = escrow::create(alice, carol, XRP(500));
+        XRPAmount const txnFees = createFeeFor(env, bytecode);
+
+        // Success situations
+        {
+            // Bytecode + CancelAfter
+            env(escrowCreate,
+                escrow::Bytecode(bytecode),
+                escrow::kCancelTime(env.now() + 20s),
+                Fee(txnFees));
+            env.close();
+        }
+        {
+            // Bytecode + Condition + CancelAfter
+            env(escrowCreate,
+                escrow::Bytecode(bytecode),
+                escrow::kCancelTime(env.now() + 30s),
+                escrow::kCondition(escrow::kCb1),
+                Fee(txnFees));
+            env.close();
+        }
+        {
+            // Bytecode + FinishAfter + CancelAfter
+            env(escrowCreate,
+                escrow::Bytecode(bytecode),
+                escrow::kCancelTime(env.now() + 40s),
+                escrow::kFinishTime(env.now() + 2s),
+                Fee(txnFees));
+            env.close();
+        }
+        {
+            // Bytecode + Data + CancelAfter
+            env(escrowCreate,
+                escrow::Bytecode(bytecode),
+                escrow::Data("00112233"),
+                escrow::kCancelTime(env.now() + 50s),
+                Fee(txnFees));
+            env.close();
+        }
+
+        // Failure situations (i.e. all other combinations)
+        {
+            // only Bytecode
+            env(escrowCreate, escrow::Bytecode(bytecode), Fee(txnFees), Ter(temBAD_EXPIRATION));
+            env.close();
+        }
+        {
+            // Bytecode + FinishAfter
+            env(escrowCreate,
+                escrow::Bytecode(bytecode),
+                escrow::kFinishTime(env.now() + 2s),
+                Fee(txnFees),
+                Ter(temBAD_EXPIRATION));
+            env.close();
+        }
+        {
+            // Bytecode + Condition
+            env(escrowCreate,
+                escrow::Bytecode(bytecode),
+                escrow::kCondition(escrow::kCb1),
+                Fee(txnFees),
+                Ter(temBAD_EXPIRATION));
+            env.close();
+        }
+        {
+            // Bytecode 0 length
+            env(escrowCreate,
+                escrow::Bytecode(""),
+                escrow::kCancelTime(env.now() + 60s),
+                Fee(txnFees),
+                Ter(temMALFORMED));
+            env.close();
+        }
+        {
+            // Not enough fees
+            env(escrowCreate,
+                escrow::Bytecode(bytecode),
+                escrow::kCancelTime(env.now() + 70s),
+                Fee(txnFees - 1),
+                Ter(telINSUF_FEE_P));
+            env.close();
+        }
+    }
+
+    void
+    testCreateFeeAndReserve(FeatureBitset features)
+    {
+        testcase("EscrowCreate fee and reserve");
+
+        using namespace jtx;
+        using namespace std::chrono;
+
+        Account const alice{"alice"};
+        Account const carol{"carol"};
+
+        {
+            // The fee scales with the bytecode: ten base fees plus five drops
+            // per byte, and a drop short of it is refused.
+            Env env(*this, features);
+            env.fund(XRP(5000), alice, carol);
+            env.close();
+
+            auto const bytecode = bytecodeOfSize(1'000);
+            auto const escrowCreate = escrow::create(alice, carol, XRP(500));
+            auto const fee = createFeeFor(env, bytecode);
+            BEAST_EXPECT(fee == env.current()->fees().base * 10 + 5'000);
+
+            env(escrowCreate,
+                escrow::Bytecode(bytecode),
+                escrow::kCancelTime(env.now() + 100s),
+                Fee(fee - 1),
+                Ter(telINSUF_FEE_P));
+            env.close();
+
+            auto const seq = env.seq(alice);
+            env(escrowCreate,
+                escrow::Bytecode(bytecode),
+                escrow::Data("00112233"),
+                escrow::kCancelTime(env.now() + 100s),
+                Fee(fee));
+            env.close();
+
+            // The ledger entry carries both fields.
+            auto const sle = env.le(keylet::escrow(alice, SeqProxy::rawSequence(seq)));
+            if (BEAST_EXPECT(sle))
+            {
+                BEAST_EXPECT(sle->isFieldPresent(sfBytecode));
+                BEAST_EXPECT(strHex(sle->getFieldVL(sfBytecode)) == bytecode);
+                BEAST_EXPECT(strHex(sle->getFieldVL(sfData)) == "00112233");
+            }
+        }
+
+        {
+            // The reserve is one owner increment per started 500 bytes of
+            // bytecode.
+            Env env(*this, features);
+            env.fund(XRP(5000), alice, carol);
+            env.close();
+
+            std::uint32_t expectedOwnerCount = 0;
+            for (auto const size : {
+                     std::size_t{64},
+                     std::size_t{500},
+                     std::size_t{501},
+                     std::size_t{1'000},
+                     std::size_t{1'001},
+                 })
+            {
+                auto const bytecode = bytecodeOfSize(size);
+                env(escrow::create(alice, carol, XRP(100)),
+                    escrow::Bytecode(bytecode),
+                    escrow::kCancelTime(env.now() + 1000s),
+                    Fee(createFeeFor(env, bytecode)));
+                env.close();
+
+                expectedOwnerCount += (size + 499) / 500;
+                BEAST_EXPECTS(
+                    env.ownerCount(alice) == expectedOwnerCount,
+                    std::to_string(size) + " bytes: " + std::to_string(env.ownerCount(alice)));
+            }
+        }
+
+        {
+            // A bytecode escrow the owner cannot reserve is refused, where the
+            // same escrow without bytecode would have been accepted.
+            Env env(*this, features);
+            // Base 200 XRP + 50 XRP per owner object, from the unit-test
+            // config. Enough for one owner object, not for two.
+            env.fund(XRP(300), alice, carol);
+            env.close();
+
+            auto const bytecode = bytecodeOfSize(1'000);
+            env(escrow::create(alice, carol, XRP(20)),
+                escrow::Bytecode(bytecode),
+                escrow::kCancelTime(env.now() + 100s),
+                Fee(createFeeFor(env, bytecode)),
+                Ter(tecINSUFFICIENT_RESERVE));
+            env.close();
+            BEAST_EXPECT(env.ownerCount(alice) == 0);
+
+            // The same escrow without bytecode costs one increment and fits.
+            env(escrow::create(alice, carol, XRP(20)),
+                escrow::kFinishTime(env.now() + 10s),
+                escrow::kCancelTime(env.now() + 100s));
+            env.close();
+            BEAST_EXPECT(env.ownerCount(alice) == 1);
+        }
+
+        {
+            // After the lock, an XRP escrow's owner must still hold the
+            // reserve the bytecode costs, not the single increment a plain
+            // escrow costs.
+            Env env(*this, features);
+            Account const dave{"dave"};
+            Account const erin{"erin"};
+            env.fund(XRP(5000), carol);
+            env.close();
+
+            auto const bytecode = bytecodeOfSize(600);  // two increments
+            auto const fee = createFeeFor(env, bytecode);
+            auto const amount = XRP(1'000);
+            auto const fees = env.current()->fees();
+
+            // One increment short after the lock.
+            env.fund(
+                STAmount{fees.accountReserve(1, 1) + amount.value().xrp() + fee}, noripple(dave));
+            // Exactly enough after the lock.
+            env.fund(
+                STAmount{fees.accountReserve(2, 1) + amount.value().xrp() + fee}, noripple(erin));
+            env.close();
+
+            env(escrow::create(dave, carol, amount),
+                escrow::Bytecode(bytecode),
+                escrow::kCancelTime(env.now() + 100s),
+                Fee(fee),
+                Ter(tecUNFUNDED));
+            env(escrow::create(erin, carol, amount),
+                escrow::Bytecode(bytecode),
+                escrow::kCancelTime(env.now() + 100s),
+                Fee(fee));
+            env.close();
+            BEAST_EXPECT(env.ownerCount(dave) == 0);
+            BEAST_EXPECT(env.ownerCount(erin) == 2);
+        }
+    }
+
+    void
+    testFinishPreflight(FeatureBitset features)
+    {
+        testcase("EscrowFinish preflight");
+
+        using namespace jtx;
+        using namespace std::chrono;
+
+        Account const alice{"alice"};
+        Account const carol{"carol"};
+
+        {
+            // featureSmartEscrow disabled
+            Env env(*this, features - featureSmartEscrow);
+            env.fund(XRP(5000), alice, carol);
+            env(escrow::finish(carol, alice, 1),
+                Fee(env.current()->fees().base + 1000),
+                escrow::Gas(4),
+                Ter(temDISABLED));
+            env.close();
+        }
+
+        {
+            // Gas > gas limit
+            Env env(*this, votingFor(Keys::kGasLimit, 1'000), features);  // in gas
+            env.fund(XRP(5000), alice, carol);
+            env.close();
+
+            // Gas above the voted limit is checked against the escrow it
+            // would run, so there has to be one.
+            auto const bytecode = bytecodeOfSize(64);
+            auto const seq = env.seq(alice);
+            env(escrow::create(alice, carol, XRP(500)),
+                escrow::Bytecode(bytecode),
+                escrow::kCancelTime(env.now() + 100'000s),
+                Fee(createFeeFor(env, bytecode)));
+            closePastFlagLedger(env);
+
+            auto const gas = 1'001;
+            env(escrow::finish(carol, alice, seq),
+                Fee(finishFeeFor(env, gas)),
+                escrow::Gas(gas),
+                Ter(tefEXCEEDS_LIMIT));
+        }
+
+        {
+            // Gas of 0
+            Env env(*this, features);
+            env.fund(XRP(5000), alice, carol);
+            env.close();
+            env(escrow::finish(carol, alice, 1),
+                Fee(env.current()->fees().base + 1000),
+                escrow::Gas(0),
+                Ter(temBAD_LIMIT));
+        }
+
+        {
+            // Gas above the protocol ceiling, refused before any view is read
+            Env env(*this, features);
+            env.fund(XRP(5000), alice, carol);
+            env.close();
+            env(escrow::finish(carol, alice, 1),
+                Fee(env.current()->fees().base + 1000),
+                escrow::Gas(kMaxGasLimit + 1),
+                Ter(temBAD_LIMIT));
+        }
+
+        {
+            // WASM compute disabled after the escrow was created.
+            Env env(*this, votingFor(Keys::kGasLimit, 0), features);
+            env.fund(XRP(5000), alice, carol);
+            env.close();
+
+            auto const bytecode = bytecodeOfSize(64);
+            auto const seq = env.seq(alice);
+            env(escrow::create(alice, carol, XRP(500)),
+                escrow::Bytecode(bytecode),
+                escrow::kCancelTime(env.now() + 100'000s),
+                Fee(createFeeFor(env, bytecode)));
+            closePastFlagLedger(env);
+
+            auto const gas = 1'000;
+            env(escrow::finish(carol, alice, seq),
+                escrow::Gas(gas),
+                Fee(finishFeeFor(env, gas)),
+                Ter(tefTEMP_DISABLED));
+        }
+    }
+
+    void
+    testFinishBytecodePairing(FeatureBitset features)
+    {
+        testcase("EscrowFinish Bytecode and Gas must agree");
+
+        using namespace jtx;
+        using namespace std::chrono;
+
+        Account const alice{"alice"};
+        Account const carol{"carol"};
+
+        Env env(*this, features);
+
+        // Run past the flag ledger so that a Fee change vote occurs and
+        // updates FeeSettings. (It also activates all supported amendments.)
+        for (auto i = env.current()->seq(); i <= 257; ++i)
+            env.close();
+
+        env.fund(XRP(5000), alice, carol);
+
+        auto const bytecode = bytecodeOfSize(64);
+        auto const seq = env.seq(alice);
+        env(escrow::create(alice, carol, XRP(500)),
+            escrow::Bytecode(bytecode),
+            escrow::kCancelTime(env.now() + 100s),
+            Fee(createFeeFor(env, bytecode)));
+        env.close();
+
+        {
+            // Bytecode on the escrow, no Gas on the finish
+            env(escrow::finish(carol, alice, seq), Ter(tefBYTECODE_NOT_INCLUDED));
+        }
+
+        {
+            // Gas on the finish, no Bytecode on the escrow
+            auto const plainSeq = env.seq(alice);
+            env(escrow::create(alice, carol, XRP(500)),
+                escrow::kFinishTime(env.now() + 10s),
+                escrow::kCancelTime(env.now() + 100s));
+            env.close();
+
+            auto const gas = 100;
+            env(escrow::finish(carol, alice, plainSeq),
+                Fee(finishFeeFor(env, gas)),
+                escrow::Gas(gas),
+                Ter(tefNO_BYTECODE));
+        }
+    }
+
+    void
+    testFinishFee(FeatureBitset features)
+    {
+        testcase("EscrowFinish fee");
+
+        using namespace jtx;
+        using namespace std::chrono;
+
+        Account const alice{"alice"};
+        Account const carol{"carol"};
+
+        Env env(
+            *this,
+            envconfig([](std::unique_ptr<Config> cfg) {
+                cfg->fees.gasPrice = 1'000'000;  // 1 drop per gas
+                return cfg;
+            }),
+            features);
+        // Run past the flag ledger so that a Fee change vote occurs and
+        // updates FeeSettings. (It also activates all supported amendments.)
+        for (auto i = env.current()->seq(); i <= 257; ++i)
+            env.close();
+
+        env.fund(XRP(5000), alice, carol);
+
+        auto const bytecode = bytecodeOfSize(64);
+        auto const seq = env.seq(alice);
+        env(escrow::create(alice, carol, XRP(1000)),
+            escrow::Bytecode(bytecode),
+            escrow::kCancelTime(env.now() + 100s),
+            Fee(createFeeFor(env, bytecode)));
+        env.close();
+
+        // A large gas allowance costs more than the allowance itself, and does
+        // not wrap.
+        auto const gas = 996'433;
+        auto const fee = finishFeeFor(env, gas);
+        BEAST_EXPECT(fee.drops() > gas);
+        // At one drop per gas the cost divides evenly, so no drop is added.
+        BEAST_EXPECT(fee == env.current()->fees().base + gas);
+
+        // Intentional low value to test overflow handling
+        env(escrow::finish(carol, alice, seq),
+            Fee(drops(30)),
+            escrow::Gas(gas),
+            Ter(telINSUF_FEE_P));
+
+        env(escrow::finish(carol, alice, seq), Fee(fee - 1), escrow::Gas(gas), Ter(telINSUF_FEE_P));
+
+        // TODO(SmartEscrow): tesSUCCESS once the WASM engine lands. Until then
+        // the fee is charged and the run reports that it could not happen.
+        env(escrow::finish(carol, alice, seq),
+            Fee(fee),
+            escrow::Gas(gas),
+            Ter(tecFAILED_PROCESSING));
+
+        {
+            // A gas cost of a fraction of a drop rounds up to a whole drop:
+            // two gas at one micro-drop each costs one drop, not zero, and not
+            // one drop per gas.
+            Env env(*this, votingFor(Keys::kGasPrice, 1), features);
+            env.fund(XRP(5000), alice, carol);
+            env.close();
+
+            auto const seq = env.seq(alice);
+            env(escrow::create(alice, carol, XRP(1000)),
+                escrow::Bytecode(bytecode),
+                escrow::kCancelTime(env.now() + 100'000s),
+                Fee(createFeeFor(env, bytecode)));
+            closePastFlagLedger(env);
+            BEAST_EXPECT(env.current()->fees().gasPrice == 1);
+
+            auto const base = env.current()->fees().base;
+            env(escrow::finish(carol, alice, seq), Fee(base), escrow::Gas(2), Ter(telINSUF_FEE_P));
+            env(escrow::finish(carol, alice, seq),
+                Fee(base + 1),
+                escrow::Gas(2),
+                Ter(tecFAILED_PROCESSING));
+        }
+    }
+
+    void
+    testFinishWithoutEngine(FeatureBitset features)
+    {
+        testcase("EscrowFinish has no WASM engine");
+
+        using namespace jtx;
+        using namespace std::chrono;
+
+        Account const alice{"alice"};
+        Account const carol{"carol"};
+
+        Env env(*this, features);
+        env.fund(XRP(5000), alice, carol);
+        env.close();
+
+        auto const bytecode = bytecodeOfSize(1'000);
+        auto const seq = env.seq(alice);
+        env(escrow::create(alice, carol, XRP(500)),
+            escrow::Bytecode(bytecode),
+            escrow::kCancelTime(env.now() + 20s),
+            Fee(createFeeFor(env, bytecode)));
+        env.close();
+        BEAST_EXPECT(env.ownerCount(alice) == 2);
+
+        // TODO(SmartEscrow): the contract decides this once the WASM engine
+        // lands - tesSUCCESS on accept, tecBYTECODE_REJECTED on reject.
+        auto const gas = 1'000;
+        env(escrow::finish(carol, alice, seq),
+            Fee(finishFeeFor(env, gas)),
+            escrow::Gas(gas),
+            Ter(tecFAILED_PROCESSING));
+        env.close();
+
+        // The escrow and its reserve survive.
+        BEAST_EXPECT(env.le(keylet::escrow(alice, SeqProxy::rawSequence(seq))));
+        BEAST_EXPECT(env.ownerCount(alice) == 2);
+
+        // Cancelling returns the whole reserve, not just one increment.
+        env.close(30s);
+        env(escrow::cancel(carol, alice, seq));
+        env.close();
+        BEAST_EXPECT(!env.le(keylet::escrow(alice, SeqProxy::rawSequence(seq))));
+        BEAST_EXPECT(env.ownerCount(alice) == 0);
+    }
+
+    void
+    testFinishReleasesReserve(FeatureBitset features)
+    {
+        testcase("EscrowFinish releases the reserve");
+
+        using namespace jtx;
+        using namespace std::chrono;
+
+        Account const alice{"alice"};
+        Account const carol{"carol"};
+
+        // Without featureSponsor and fixCleanup3_4_0, the reserve is released
+        // after delivery rather than before.
+        Env env(*this, features - featureSponsor - fixCleanup3_4_0);
+        env.fund(XRP(5000), alice, carol);
+        env.close();
+
+        auto const seq = env.seq(alice);
+        env(escrow::create(alice, carol, XRP(500)), escrow::kFinishTime(env.now() + 1s));
+        env.close();
+        BEAST_EXPECT(env.ownerCount(alice) == 1);
+
+        env(escrow::finish(carol, alice, seq));
+        env.close();
+        BEAST_EXPECT(!env.le(keylet::escrow(alice, SeqProxy::rawSequence(seq))));
+        BEAST_EXPECT(env.ownerCount(alice) == 0);
+    }
+
+    void
+    testWithFeats(FeatureBitset features)
+    {
+        testCreatePreflight(features);
+        testCreateFeeAndReserve(features);
+        testFinishPreflight(features);
+        testFinishBytecodePairing(features);
+        testFinishFee(features);
+        testFinishWithoutEngine(features);
+        testFinishReleasesReserve(features);
+    }
+
+public:
+    void
+    run() override
+    {
+        using namespace test::jtx;
+        FeatureBitset const all{testableAmendments()};
+        testWithFeats(all);
+    }
+};
+
+BEAST_DEFINE_TESTSUITE(EscrowSmart, app, xrpl);
+
+}  // namespace xrpl::test

src/test/app/Escrow_test.cpp

@@ -1524,7 +1524,7 @@ struct Escrow_test : public beast::unit_test::Suite
         Account const alice{"alice"};
         Account const bob{"bob"};
         Account const carol{"carol"};
-        Account const dillon{"dillon "};
+        Account const dillon{"dillon"};
         Account const zelda{"zelda"};
 
         char const credType[] = "abcde";
@@ -1682,6 +1682,8 @@ public:
         testWithFeats(all);
         testWithFeats(all - featureTokenEscrow);
         testWithFeats(all - fixCleanup3_5_0);
+        testWithFeats(all - featureSmartEscrow);
+        testWithFeats(all - featureTokenEscrow - featureSmartEscrow);
         testTags(all - fixIncludeKeyletFields);
     }
 };

src/test/app/FlowMPT_test.cpp

@@ -1215,6 +1215,61 @@ struct FlowMPT_test : public beast::unit_test::Suite
         BEAST_EXPECT(env.balance(bob, y) == y(0));
     }
 
+    void
+    testConsumeOfferOverflow(FeatureBitset features)
+    {
+        // An overflow while consuming an offer fails the strand under
+        // MPTokensV2, and the transaction with tecINTERNAL otherwise. Either
+        // way no balances change and the offer stays on the book.
+        testcase("BookStep consumeOffer overflow");
+
+        using namespace jtx;
+
+        Account const gw("gateway");
+        Account const eurGW("eur_gateway");
+        Account const maker("maker");
+        Account const alice("alice");
+        Account const bob("bob");
+
+        for (auto const& testFeatures : {features, features - featureMPTokensV2})
+        {
+            Env env(*this, testFeatures);
+
+            auto const withV2 = testFeatures[featureMPTokensV2];
+
+            env.fund(XRP(10'000), gw, eurGW, maker, alice, bob);
+            env.close();
+
+            auto const usd = gw["USD"];
+            auto const eur = eurGW["EUR"];
+            STAmount const usdMax{usd.issue(), STAmount::kMaxValue, STAmount::kMaxOffset};
+            STAmount const usdIn{usd.issue(), 1, 90};
+
+            env.trust(usdMax, maker, alice);
+            env.trust(eur(1'000), maker, bob);
+            env.close();
+
+            env(pay(gw, maker, usdMax));
+            env(pay(gw, alice, usdIn));
+            env(pay(eurGW, maker, eur(100)));
+            env(offer(maker, usdIn, eur(100)));
+            env.close();
+
+            env(pay(alice, bob, eur(100)),
+                Path(~eur),
+                Sendmax(usdIn),
+                Ter(withV2 ? TER{tecPATH_PARTIAL} : TER{tecINTERNAL}));
+            env.close();
+
+            env.require(
+                Balance(bob, eur(0)),
+                Balance(maker, eur(100)),
+                Balance(maker, usdMax),
+                Balance(alice, usdIn));
+            BEAST_EXPECT(isOffer(env, maker, usdIn, eur(100)));
+        }
+    }
+
     void
     testFalseDry(FeatureBitset features)
     {
@@ -3008,6 +3063,7 @@ struct FlowMPT_test : public beast::unit_test::Suite
         testBookStepInputAboveMaximumAmount(features);
         testBookStepInputAboveMaximumAmountWithFee(features);
         testBookStepMissingIssuance(features);
+        testConsumeOfferOverflow(features);
         testSelfPayment1(features);
         testSelfPayment2(features);
         testSelfFundedXRPEndpoint(false, features);
@@ -3016,6 +3072,85 @@ struct FlowMPT_test : public beast::unit_test::Suite
         testReExecuteDirectStep(features);
         testSelfPayLowQualityOffer(features);
         testLockedMidPathHolder(features);
+        testIssuerSourceMPTLoop(features);
+    }
+
+    void
+    testIssuerSourceMPTLoop(FeatureBitset features)
+    {
+        // An issuer paying with its own MPT may not route it back through a
+        // book that outputs the same MPT. It would issue at the first book
+        // and again after the second, and with the issuer's own offer in
+        // the second book the engine could not keep the sum within
+        // MaximumAmount. Holders already get temBAD_PATH_LOOP for this.
+        testcase("Issuer-sourced payment looping through its own MPT");
+
+        using namespace jtx;
+
+        Account const gw{"gw"};
+        Account const alice{"alice"};
+        Account const c1{"c1"};
+        Account const e1{"e1"};
+        Account const dan{"dan"};
+
+        Env env(*this, features);
+        env.fund(XRP(1'000), gw, alice, c1, e1, dan);
+        env.close();
+
+        MPT const x =
+            MPTTester({.env = env, .issuer = gw, .holders = {alice, c1, e1, dan}, .maxAmt = 100});
+        auto const eur = gw["EUR"];
+        auto const usd = gw["USD"];
+        env(trust(e1, eur(1'000)));
+        env(trust(e1, usd(1'000)));
+        env(trust(dan, eur(1'000)));
+        env(pay(gw, e1, eur(1'000)));
+        env(pay(gw, e1, usd(1'000)));
+        env(pay(gw, alice, x(10)));
+        env.close();
+
+        // Liquidity for every path below, arranged so nothing crosses at
+        // creation.
+        env(offer(gw, XRP(60), x(30)));    // issuer sells x for XRP
+        env(offer(gw, usd(100), x(100)));  // issuer sells x for usd
+        env.close();
+        env(offer(c1, x(100), XRP(100)));  // buys x for XRP
+        env(offer(e1, XRP(70), usd(70)));  // sells usd for XRP
+        env(offer(e1, x(100), eur(100)));  // sells eur for x
+        env.close();
+        BEAST_EXPECT(expectOffers(env, gw, 2));
+        BEAST_EXPECT(expectOffers(env, c1, 1));
+        BEAST_EXPECT(expectOffers(env, e1, 2));
+
+        auto const flags = Txflags(tfNoRippleDirect | tfPartialPayment);
+
+        // x -> XRP -> x, the issuer's own offer feeds the endpoint
+        env(pay(gw, dan, x(100)), Sendmax(x(100)), Path(~XRP, ~x), flags, Ter(temBAD_PATH_LOOP));
+        // x -> XRP -> x -> eur, the issuer's own offer feeds a third book
+        env(pay(gw, dan, eur(100)),
+            Sendmax(x(100)),
+            Path(~XRP, ~x, ~eur),
+            flags,
+            Ter(temBAD_PATH_LOOP));
+        // x -> XRP -> usd -> x, a limiting book before the issuer's own offer
+        env(pay(gw, dan, x(100)),
+            Sendmax(x(100)),
+            Path(~XRP, ~usd, ~x),
+            flags,
+            Ter(temBAD_PATH_LOOP));
+        // Same loop from a holder is already rejected
+        env(pay(alice, dan, x(10)), Sendmax(x(10)), Path(~XRP, ~x), flags, Ter(temBAD_PATH_LOOP));
+        env.close();
+
+        BEAST_EXPECT(env.balance(gw, x) == x(-10));
+        BEAST_EXPECT(env.balance(c1, x) == x(0));
+        BEAST_EXPECT(env.balance(dan, x) == x(0));
+
+        // The issuer paying with another asset may still take its own offer
+        env(pay(gw, dan, x(50)), Sendmax(usd(50)), Path(~x), flags);
+        env.close();
+        BEAST_EXPECT(env.balance(dan, x) == x(50));
+        BEAST_EXPECT(env.balance(gw, x) == x(-60));
     }
 
     void

src/test/app/MPToken_test.cpp

@@ -39,6 +39,7 @@
 #include <xrpl/ledger/helpers/MPTokenHelpers.h>
 #include <xrpl/ledger/helpers/TokenHelpers.h>
 #include <xrpl/protocol/Asset.h>
+#include <xrpl/protocol/ErrorCodes.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/IOUAmount.h>
 #include <xrpl/protocol/Indexes.h>
@@ -994,8 +995,9 @@ class MPToken_test : public beast::unit_test::Suite
             test::jtx::MPT const mpT1("MPT", makeMptID(env.seq(alice) + 10, alice));
             err = !mpTokensV2 ? Ter(temMALFORMED) : Ter(tecOBJECT_NOT_FOUND);
             env(pay(alice, carol, mpT1(100)), Sendmax(mpt(100)), err);
-            // "paths" is invalid in V1
-            err = !mpTokensV2 ? Ter(temMALFORMED) : Ter(tesSUCCESS);
+            // "paths" is invalid in V1. In V2 any path from the issuer back
+            // to its own MPT is a loop, like it is for a holder.
+            err = !mpTokensV2 ? Ter(temMALFORMED) : Ter(temBAD_PATH_LOOP);
             env(pay(alice, carol, mpt(100)), Path(~usd), err);
         }
 
@@ -1019,6 +1021,7 @@ class MPToken_test : public beast::unit_test::Suite
             payment[jss::build_path] = true;
             auto jrr = env.rpc("json", "submit", to_string(payment));
             BEAST_EXPECT(jrr[jss::result][jss::error] == "invalidParams");
+            BEAST_EXPECT(jrr[jss::result][jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(
                 jrr[jss::result][jss::error_message] ==
                 "Field 'build_path' not allowed in this context.");
@@ -1580,6 +1583,8 @@ class MPToken_test : public beast::unit_test::Suite
             jv[jss::tx_json][jss::Amount][jss::value] = std::to_string(kMaxMpTokenAmount + 1);
             auto const jrr = env.rpc("json", "submit", to_string(jv));
             BEAST_EXPECT(jrr[jss::result][jss::error] == "invalidParams");
+            BEAST_EXPECT(jrr[jss::result][jss::error_code] == RpcInvalidParams);
+            BEAST_EXPECT(jrr[jss::result][jss::error_message] == "Invalid field 'tx_json.Amount'.");
         }
 
         // Pay maximum amount with the transfer fee, SendMax, and
@@ -1944,6 +1949,8 @@ class MPToken_test : public beast::unit_test::Suite
                 jtx.stx->add(s);
                 auto jrr = env.rpc("submit", strHex(s.slice()));
                 BEAST_EXPECT(jrr[jss::result][jss::error] == "invalidTransaction");
+                BEAST_EXPECT(!jrr[jss::result].isMember(jss::error_code));
+                BEAST_EXPECT(jrr[jss::result][jss::error_message].isNull());
 
                 // tx is unsigned
                 json::Value jv1;
@@ -1951,9 +1958,13 @@ class MPToken_test : public beast::unit_test::Suite
                 jv1[jss::tx_json] = jv;
                 jrr = env.rpc("json", "submit", to_string(jv1));
                 BEAST_EXPECT(jrr[jss::result][jss::error] == "invalidParams");
+                BEAST_EXPECT(jrr[jss::result][jss::error_code] == RpcInvalidParams);
+                BEAST_EXPECT(jrr[jss::result][jss::error_message] == "Amount can not be MPT.");
 
                 jrr = env.rpc("json", "sign", to_string(jv1));
                 BEAST_EXPECT(jrr[jss::result][jss::error] == "invalidParams");
+                BEAST_EXPECT(jrr[jss::result][jss::error_code] == RpcInvalidParams);
+                BEAST_EXPECT(jrr[jss::result][jss::error_message] == "Amount can not be MPT.");
             };
             auto setMPTFields = [&](SField const& field, json::Value& jv, bool withAmount = true) {
                 jv[jss::Asset] = toJson(xrpIssue());
@@ -3197,6 +3208,9 @@ class MPToken_test : public beast::unit_test::Suite
             jv1[jss::tx_json] = jv;
             auto const jrr = env.rpc("json", "submit", to_string(jv1));
             BEAST_EXPECT(jrr[jss::result][jss::error] == "invalidParams");
+            BEAST_EXPECT(jrr[jss::result][jss::error_code] == RpcInvalidParams);
+            BEAST_EXPECT(
+                jrr[jss::result][jss::error_message] == "Field 'tx_json.Amount' has invalid data.");
         }
     }
 

src/test/app/MultiSign_test.cpp

@@ -31,6 +31,7 @@
 #include <xrpl/config/Constants.h>
 #include <xrpl/json/json_value.h>
 #include <xrpl/json/to_string.h>
+#include <xrpl/protocol/ErrorCodes.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/Indexes.h>
 #include <xrpl/protocol/KeyType.h>
@@ -586,6 +587,7 @@ public:
             auto jrr = env.rpc("json", "sign_for", to_string(jvOne))[jss::result];
             BEAST_EXPECT(jrr[jss::status] == "error");
             BEAST_EXPECT(jrr[jss::error] == "invalidParams");
+            BEAST_EXPECT(jrr[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(
                 jrr[jss::error_message] ==
                 "When multi-signing 'tx_json.SigningPubKey' must be empty.");
@@ -613,6 +615,7 @@ public:
             jrr = env.rpc("json", "submit_multisigned", to_string(jvSubmit))[jss::result];
             BEAST_EXPECT(jrr[jss::status] == "error");
             BEAST_EXPECT(jrr[jss::error] == "invalidParams");
+            BEAST_EXPECT(jrr[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(
                 jrr[jss::error_message] == "Invalid Fee field.  Fees must be greater than zero.");
         }
@@ -639,6 +642,7 @@ public:
             jrr = env.rpc("json", "submit_multisigned", to_string(jvSubmit))[jss::result];
             BEAST_EXPECT(jrr[jss::status] == "error");
             BEAST_EXPECT(jrr[jss::error] == "internal");
+            BEAST_EXPECT(jrr[jss::error_code] == RpcInternal);
             BEAST_EXPECT(jrr[jss::error_message] == "Internal error.");
         }
 
@@ -651,6 +655,8 @@ public:
             auto jrr = env.rpc("json", "sign_for", to_string(jv))[jss::result];
             BEAST_EXPECT(jrr[jss::status] == "error");
             BEAST_EXPECT(jrr[jss::error] == "masterDisabled");
+            BEAST_EXPECT(jrr[jss::error_code] == RpcMasterDisabled);
+            BEAST_EXPECT(jrr[jss::error_message] == "Master key is disabled.");
             env.close();
             BEAST_EXPECT(env.seq(alice) == aliceSeq);
         }
@@ -690,12 +696,16 @@ public:
             auto jrr = env.rpc("json", "sign_for", to_string(jv))[jss::result];
             BEAST_EXPECT(jrr[jss::status] == "error");
             BEAST_EXPECT(jrr[jss::error] == "srcActMalformed");
+            BEAST_EXPECT(jrr[jss::error_code] == RpcSrcActMalformed);
+            BEAST_EXPECT(jrr[jss::error_message] == "Invalid field 'tx_json.Account'.");
 
             Account const jimmy{"jimmy"};
             jv[jss::tx_json][jss::Account] = jimmy.human();
             jrr = env.rpc("json", "sign_for", to_string(jv))[jss::result];
             BEAST_EXPECT(jrr[jss::status] == "error");
             BEAST_EXPECT(jrr[jss::error] == "srcActNotFound");
+            BEAST_EXPECT(jrr[jss::error_code] == RpcSrcActNotFound);
+            BEAST_EXPECT(jrr[jss::error_message] == "Source account not found.");
         }
 
         {
@@ -706,6 +716,7 @@ public:
             auto jrr = env.rpc("json", "submit_multisigned", to_string(jv))[jss::result];
             BEAST_EXPECT(jrr[jss::status] == "error");
             BEAST_EXPECT(jrr[jss::error] == "invalidParams");
+            BEAST_EXPECT(jrr[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(jrr[jss::error_message] == "tx_json.Signers array may not be empty.");
             env.close();
             BEAST_EXPECT(env.seq(alice) == aliceSeq);
@@ -1068,6 +1079,9 @@ public:
             STTx local = *tx.stx;
             local.setFieldVL(sfSigningPubKey, Blob());  // Empty SigningPubKey
             auto const info = submitSTTx(local);
+            BEAST_EXPECT(info[jss::result][jss::error] == "invalidTransaction");
+            BEAST_EXPECT(!info[jss::result].isMember(jss::error_code));
+            BEAST_EXPECT(info[jss::result][jss::error_message].isNull());
             BEAST_EXPECT(
                 info[jss::result][jss::error_exception] ==
                 "fails local checks: Empty SigningPubKey.");
@@ -1082,6 +1096,9 @@ public:
             local.setFieldVL(sfTxnSignature, badSig);
             // Signature should fail.
             auto const info = submitSTTx(local);
+            BEAST_EXPECT(info[jss::result][jss::error] == "invalidTransaction");
+            BEAST_EXPECT(!info[jss::result].isMember(jss::error_code));
+            BEAST_EXPECT(info[jss::result][jss::error_message].isNull());
             BEAST_EXPECT(
                 info[jss::result][jss::error_exception] ==
                 "fails local checks: Invalid signature.");
@@ -1095,6 +1112,9 @@ public:
             local.setFieldU32(sfSequence, seq + 1);
             // Signature should fail.
             auto const info = submitSTTx(local);
+            BEAST_EXPECT(info[jss::result][jss::error] == "invalidTransaction");
+            BEAST_EXPECT(!info[jss::result].isMember(jss::error_code));
+            BEAST_EXPECT(info[jss::result][jss::error_message].isNull());
             BEAST_EXPECT(
                 info[jss::result][jss::error_exception] ==
                 "fails local checks: Invalid signature.");
@@ -1105,6 +1125,9 @@ public:
             STTx local = *tx.stx;
             local[sfSigningPubKey] = alice.pk();  // Insert sfSigningPubKey
             auto const info = submitSTTx(local);
+            BEAST_EXPECT(info[jss::result][jss::error] == "invalidTransaction");
+            BEAST_EXPECT(!info[jss::result].isMember(jss::error_code));
+            BEAST_EXPECT(info[jss::result][jss::error_message].isNull());
             BEAST_EXPECT(
                 info[jss::result][jss::error_exception] ==
                 "fails local checks: Cannot both single- and multi-sign.");
@@ -1116,6 +1139,9 @@ public:
             local.sign(alice.pk(), alice.sk());
             local.setFieldVL(sfSigningPubKey, Blob());  // Empty SigningPubKey
             auto const info = submitSTTx(local);
+            BEAST_EXPECT(info[jss::result][jss::error] == "invalidTransaction");
+            BEAST_EXPECT(!info[jss::result].isMember(jss::error_code));
+            BEAST_EXPECT(info[jss::result][jss::error_message].isNull());
             BEAST_EXPECT(
                 info[jss::result][jss::error_exception] ==
                 "fails local checks: Cannot both single- and multi-sign.");
@@ -1131,6 +1157,9 @@ public:
             signer.setFieldVL(sfTxnSignature, badSig);
             // Signature should fail.
             auto const info = submitSTTx(local);
+            BEAST_EXPECT(info[jss::result][jss::error] == "invalidTransaction");
+            BEAST_EXPECT(!info[jss::result].isMember(jss::error_code));
+            BEAST_EXPECT(info[jss::result][jss::error_message].isNull());
             BEAST_EXPECT(
                 info[jss::result][jss::error_exception].asString().contains(
                     "Invalid signature on account r"));
@@ -1141,6 +1170,9 @@ public:
             STTx local = *tx.stx;
             local.peekFieldArray(sfSigners).clear();  // Empty Signers array.
             auto const info = submitSTTx(local);
+            BEAST_EXPECT(info[jss::result][jss::error] == "invalidTransaction");
+            BEAST_EXPECT(!info[jss::result].isMember(jss::error_code));
+            BEAST_EXPECT(info[jss::result][jss::error_message].isNull());
             BEAST_EXPECT(
                 info[jss::result][jss::error_exception] ==
                 "fails local checks: Invalid Signers array size.");
@@ -1186,6 +1218,9 @@ public:
                     bogie_));
             STTx const local = *tx.stx;
             auto const info = submitSTTx(local);
+            BEAST_EXPECT(info[jss::result][jss::error] == "invalidTransaction");
+            BEAST_EXPECT(!info[jss::result].isMember(jss::error_code));
+            BEAST_EXPECT(info[jss::result][jss::error_message].isNull());
             BEAST_EXPECT(
                 info[jss::result][jss::error_exception] ==
                 "fails local checks: Invalid Signers array size.");
@@ -1195,6 +1230,9 @@ public:
             JTx const tx = env.jt(noop(alice), Fee(2 * baseFee), Msig(alice));
             STTx const local = *tx.stx;
             auto const info = submitSTTx(local);
+            BEAST_EXPECT(info[jss::result][jss::error] == "invalidTransaction");
+            BEAST_EXPECT(!info[jss::result].isMember(jss::error_code));
+            BEAST_EXPECT(info[jss::result][jss::error_message].isNull());
             BEAST_EXPECT(
                 info[jss::result][jss::error_exception] ==
                 "fails local checks: Invalid multisigner.");
@@ -1204,6 +1242,9 @@ public:
             JTx const tx = env.jt(noop(alice), Fee(2 * baseFee), Msig(bogie_, bogie_));
             STTx const local = *tx.stx;
             auto const info = submitSTTx(local);
+            BEAST_EXPECT(info[jss::result][jss::error] == "invalidTransaction");
+            BEAST_EXPECT(!info[jss::result].isMember(jss::error_code));
+            BEAST_EXPECT(info[jss::result][jss::error_message].isNull());
             BEAST_EXPECT(
                 info[jss::result][jss::error_exception] ==
                 "fails local checks: Duplicate Signers not allowed.");
@@ -1217,6 +1258,9 @@ public:
             std::ranges::reverse(signers);
             // Signature should fail.
             auto const info = submitSTTx(local);
+            BEAST_EXPECT(info[jss::result][jss::error] == "invalidTransaction");
+            BEAST_EXPECT(!info[jss::result].isMember(jss::error_code));
+            BEAST_EXPECT(info[jss::result][jss::error_message].isNull());
             BEAST_EXPECT(
                 info[jss::result][jss::error_exception] ==
                 "fails local checks: Unsorted Signers array.");

src/test/app/NFToken_test.cpp

@@ -30,6 +30,7 @@
 #include <xrpl/json/to_string.h>
 #include <xrpl/ledger/OpenView.h>
 #include <xrpl/protocol/ApiVersion.h>
+#include <xrpl/protocol/ErrorCodes.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/Indexes.h>
 #include <xrpl/protocol/Protocol.h>
@@ -4653,18 +4654,22 @@ class NFTokenBaseUtil_test : public beast::unit_test::Suite
                     if (expect(
                             nftOffers.isMember(jss::result), "expected \"result\"", __FILE__, line))
                     {
-                        if (expect(
-                                nftOffers[jss::result].isMember(jss::error),
-                                "expected \"error\"",
-                                __FILE__,
-                                line))
-                        {
-                            expect(
-                                nftOffers[jss::result][jss::error].asString() == "objectNotFound",
-                                "expected \"objectNotFound\"",
-                                __FILE__,
-                                line);
-                        }
+                        json::Value const& result = nftOffers[jss::result];
+                        expect(
+                            result[jss::error].asString() == "objectNotFound",
+                            "expected \"objectNotFound\"",
+                            __FILE__,
+                            line);
+                        expect(
+                            result[jss::error_code] == RpcObjectNotFound,
+                            "expected RpcObjectNotFound",
+                            __FILE__,
+                            line);
+                        expect(
+                            result[jss::error_message] == "The requested object was not found.",
+                            "expected \"The requested object was not found.\"",
+                            __FILE__,
+                            line);
                     }
                     break;
                 }
@@ -4860,11 +4865,15 @@ class NFTokenBaseUtil_test : public beast::unit_test::Suite
             // Sell-side marker passed to nft_buy_offers.
             json::Value const result = queryWithMarker("nft_buy_offers", sellOfferIndex);
             BEAST_EXPECT(result[jss::error].asString() == "invalidParams");
+            BEAST_EXPECT(result[jss::error_code] == RpcInvalidParams);
+            BEAST_EXPECT(result[jss::error_message] == "Invalid parameters.");
         }
         {
             // Buy-side marker passed to nft_sell_offers.
             json::Value const result = queryWithMarker("nft_sell_offers", buyOfferIndex);
             BEAST_EXPECT(result[jss::error].asString() == "invalidParams");
+            BEAST_EXPECT(result[jss::error_code] == RpcInvalidParams);
+            BEAST_EXPECT(result[jss::error_message] == "Invalid parameters.");
         }
 
         // A same-side marker is still accepted.  With a single offer on each

src/test/app/OfferMPT_test.cpp

@@ -34,6 +34,7 @@
 #include <xrpl/ledger/helpers/DirectoryHelpers.h>
 #include <xrpl/protocol/AccountID.h>
 #include <xrpl/protocol/Book.h>
+#include <xrpl/protocol/ErrorCodes.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/Indexes.h>
 #include <xrpl/protocol/Issue.h>
@@ -2755,6 +2756,8 @@ public:
 
         jro = ledgerEntryOffer(env, bob, bobOfferSeq);
         BEAST_EXPECT(jro[jss::error] == "entryNotFound");
+        BEAST_EXPECT(jro[jss::error_code] == RpcEntryNotFound);
+        BEAST_EXPECT(jro[jss::error_message] == "Entry not found.");
 
         env.require(Owners(alice, 1), Owners(bob, 1));
     }
@@ -2788,6 +2791,8 @@ public:
 
             auto jro = ledgerEntryOffer(env, bob, bobOfferSeq);
             BEAST_EXPECT(jro[jss::error] == "entryNotFound");
+            BEAST_EXPECT(jro[jss::error_code] == RpcEntryNotFound);
+            BEAST_EXPECT(jro[jss::error_message] == "Entry not found.");
         };
         testHelper3TokensMix(test);
     }
@@ -2847,6 +2852,8 @@ public:
         // Verify the offer was consumed
         jro = ledgerEntryOffer(env, bob, bobOfferSeq);
         BEAST_EXPECT(jro[jss::error] == "entryNotFound");
+        BEAST_EXPECT(jro[jss::error_code] == RpcEntryNotFound);
+        BEAST_EXPECT(jro[jss::error_message] == "Entry not found.");
 
         // verify balances look right after the partial payment
         // only 300 XRP should have been payed since that's all

src/test/app/Offer_test.cpp

@@ -30,6 +30,7 @@
 #include <xrpl/json/to_string.h>
 #include <xrpl/ledger/helpers/DirectoryHelpers.h>
 #include <xrpl/protocol/AccountID.h>
+#include <xrpl/protocol/ErrorCodes.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/Indexes.h>
 #include <xrpl/protocol/Issue.h>
@@ -1707,6 +1708,8 @@ public:
 
         jro = ledgerEntryOffer(env, bob, bobOfferSeq);
         BEAST_EXPECT(jro[jss::error] == "entryNotFound");
+        BEAST_EXPECT(jro[jss::error_code] == RpcEntryNotFound);
+        BEAST_EXPECT(jro[jss::error_message] == "Entry not found.");
 
         env.require(Owners(alice, 1), Owners(bob, 1));
     }
@@ -1738,6 +1741,8 @@ public:
 
         auto jro = ledgerEntryOffer(env, bob, bobOfferSeq);
         BEAST_EXPECT(jro[jss::error] == "entryNotFound");
+        BEAST_EXPECT(jro[jss::error_code] == RpcEntryNotFound);
+        BEAST_EXPECT(jro[jss::error_message] == "Entry not found.");
     }
 
     void
@@ -1798,6 +1803,8 @@ public:
         // Verify the offer was consumed
         jro = ledgerEntryOffer(env, bob, bobOfferSeq);
         BEAST_EXPECT(jro[jss::error] == "entryNotFound");
+        BEAST_EXPECT(jro[jss::error_code] == RpcEntryNotFound);
+        BEAST_EXPECT(jro[jss::error_message] == "Entry not found.");
 
         // verify balances look right after the partial payment
         // only 300 XRP should be have been payed since that's all

src/test/app/PathMPT_test.cpp

@@ -26,6 +26,7 @@
 #include <xrpl/json/json_value.h>
 #include <xrpl/protocol/AccountID.h>
 #include <xrpl/protocol/ApiVersion.h>
+#include <xrpl/protocol/ErrorCodes.h>
 #include <xrpl/protocol/Indexes.h>
 #include <xrpl/protocol/PathAsset.h>
 #include <xrpl/protocol/SField.h>
@@ -162,7 +163,9 @@ public:
             g.signal();
         });
         BEAST_EXPECT(g.waitFor(5s));
-        BEAST_EXPECT(result.isMember(jss::error));
+        BEAST_EXPECT(result[jss::error] == "srcCurMalformed");
+        BEAST_EXPECT(result[jss::error_code] == RpcSrcCurMalformed);
+        BEAST_EXPECT(result[jss::error_message] == "Source currency is malformed.");
 
         // Test rpc::tuning::max_auto_src_cur source currencies.
         numSrc.clear();
@@ -189,7 +192,9 @@ public:
             g.signal();
         });
         BEAST_EXPECT(g.waitFor(5s));
-        BEAST_EXPECT(result.isMember(jss::error));
+        BEAST_EXPECT(result[jss::error] == "internal");
+        BEAST_EXPECT(result[jss::error_code] == RpcInternal);
+        BEAST_EXPECT(result[jss::error_message] == "Internal error.");
     }
 
     void

src/test/app/Path_test.cpp

@@ -33,6 +33,7 @@
 #include <xrpl/json/json_value.h>
 #include <xrpl/protocol/AccountID.h>
 #include <xrpl/protocol/ApiVersion.h>
+#include <xrpl/protocol/ErrorCodes.h>
 #include <xrpl/protocol/Indexes.h>
 #include <xrpl/protocol/Issue.h>
 #include <xrpl/protocol/SField.h>
@@ -318,7 +319,9 @@ public:
             g.signal();
         });
         BEAST_EXPECT(g.waitFor(5s));
-        BEAST_EXPECT(result.isMember(jss::error));
+        BEAST_EXPECT(result[jss::error] == "srcCurMalformed");
+        BEAST_EXPECT(result[jss::error_code] == RpcSrcCurMalformed);
+        BEAST_EXPECT(result[jss::error_message] == "Source currency is malformed.");
 
         // Test rpc::tuning::max_auto_src_cur source currencies.
         for (auto i = 0; i < (rpc::tuning::kMaxAutoSrcCur - 1); ++i)
@@ -341,7 +344,9 @@ public:
             g.signal();
         });
         BEAST_EXPECT(g.waitFor(5s));
-        BEAST_EXPECT(result.isMember(jss::error));
+        BEAST_EXPECT(result[jss::error] == "internal");
+        BEAST_EXPECT(result[jss::error_code] == RpcInternal);
+        BEAST_EXPECT(result[jss::error_message] == "Internal error.");
     }
 
     void

src/test/app/PayChan_test.cpp

@@ -31,6 +31,7 @@
 #include <xrpl/ledger/Dir.h>
 #include <xrpl/ledger/ReadView.h>
 #include <xrpl/protocol/ApiVersion.h>
+#include <xrpl/protocol/ErrorCodes.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/Indexes.h>
 #include <xrpl/protocol/KeyType.h>
@@ -1009,6 +1010,7 @@ struct PayChan_test : public beast::unit_test::Suite
                 auto const jrr =
                     env.rpc("json", "account_channels", to_string(params))[jss::result];
                 BEAST_EXPECT(jrr[jss::error] == "invalidParams");
+                BEAST_EXPECT(jrr[jss::error_code] == RpcInvalidParams);
                 BEAST_EXPECT(jrr[jss::error_message] == "Invalid field 'account'.");
             };
 
@@ -1028,6 +1030,7 @@ struct PayChan_test : public beast::unit_test::Suite
                 auto const jrr =
                     env.rpc("json", "account_channels", to_string(params))[jss::result];
                 BEAST_EXPECT(jrr[jss::error] == "invalidParams");
+                BEAST_EXPECT(jrr[jss::error_code] == RpcInvalidParams);
                 BEAST_EXPECT(jrr[jss::error_message] == "Invalid field 'destination_account'.");
             };
 
@@ -1038,6 +1041,55 @@ struct PayChan_test : public beast::unit_test::Suite
             testInvalidDestAccountParam(json::Value(json::ValueType::Object));
             testInvalidDestAccountParam(json::Value(json::ValueType::Array));
         }
+        {
+            // An empty destination_account is no destination at all.
+            json::Value params;
+            params[jss::account] = alice.human();
+            params[jss::destination_account] = "";
+            auto const jrr = env.rpc("json", "account_channels", to_string(params))[jss::result];
+            BEAST_EXPECT(jrr[jss::channels].size() == 1);
+            BEAST_EXPECT(jrr[jss::channels][0u][jss::channel_id] == chan1Str);
+            BEAST_EXPECT(jrr[jss::channels][0u][jss::destination_account] == bob.human());
+        }
+        {
+            // A malformed account is reported without the ledger fields.
+            json::Value params;
+            params[jss::account] = "llIIOO";
+            auto const jrr = env.rpc("json", "account_channels", to_string(params))[jss::result];
+            BEAST_EXPECT(jrr[jss::error] == "actMalformed");
+            BEAST_EXPECT(jrr[jss::error_code] == RpcActMalformed);
+            BEAST_EXPECT(jrr[jss::error_message] == "Account malformed.");
+            BEAST_EXPECT(!jrr.isMember(jss::ledger_index));
+            BEAST_EXPECT(!jrr.isMember(jss::ledger_current_index));
+        }
+        {
+            // A bad limit is reported before an account that is not found.
+            json::Value params;
+            params[jss::account] = Account("bogie").human();
+            params[jss::limit] = 0;
+            auto const jrr = env.rpc("json", "account_channels", to_string(params))[jss::result];
+            BEAST_EXPECT(jrr[jss::error] == "invalidParams");
+            BEAST_EXPECT(jrr[jss::error_code] == RpcInvalidParams);
+            BEAST_EXPECT(jrr[jss::error_message] == "Invalid field 'limit'.");
+        }
+        {
+            // A non-string marker names the field; one that does not parse does not.
+            json::Value params;
+            params[jss::account] = alice.human();
+            params[jss::marker] = 1;
+            auto const notString =
+                env.rpc("json", "account_channels", to_string(params))[jss::result];
+            BEAST_EXPECT(notString[jss::error] == "invalidParams");
+            BEAST_EXPECT(notString[jss::error_code] == RpcInvalidParams);
+            BEAST_EXPECT(notString[jss::error_message] == "Invalid field 'marker', not string.");
+
+            params[jss::marker] = "NOT_A_MARKER";
+            auto const malformed =
+                env.rpc("json", "account_channels", to_string(params))[jss::result];
+            BEAST_EXPECT(malformed[jss::error] == "invalidParams");
+            BEAST_EXPECT(malformed[jss::error_code] == RpcInvalidParams);
+            BEAST_EXPECT(malformed[jss::error_message] == "Invalid parameters.");
+        }
         {
             auto const r = env.rpc("account_channels", alice.human(), bob.human());
             BEAST_EXPECT(r[jss::result][jss::channels].size() == 1);
@@ -1181,7 +1233,34 @@ struct PayChan_test : public beast::unit_test::Suite
         {
             // degenerate case
             auto const r = testLimit(env, alice, 0);
-            BEAST_EXPECT(r.isMember(jss::error_message));
+            BEAST_EXPECT(r[jss::error] == "invalidParams");
+            BEAST_EXPECT(r[jss::error_code] == RpcInvalidParams);
+            BEAST_EXPECT(r[jss::error_message] == "Invalid field 'limit'.");
+        }
+
+        {
+            // The marker's start hint may have a leading '+', and anything after a second
+            // comma is ignored.
+            auto const first = testLimit(env, alice, 1);
+            auto const marker = first[jss::marker].asString();
+            auto const comma = marker.find(',');
+            BEAST_EXPECT(comma != std::string::npos);
+
+            auto const rest = testLimit(
+                env,
+                alice,
+                std::nullopt,
+                marker.substr(0, comma) + ",+" + marker.substr(comma + 1) + ",ignored");
+            BEAST_EXPECT(rest[jss::channels].size() == bobs.size() - 1);
+
+            std::set<std::string> found{
+                first[jss::channels][0u][jss::destination_account].asString(),
+            };
+
+            for (auto const& c : rest[jss::channels])
+                BEAST_EXPECT(found.insert(c[jss::destination_account].asString()).second);
+
+            BEAST_EXPECT(found == bobsB58);
         }
     }
 
@@ -1250,7 +1329,12 @@ struct PayChan_test : public beast::unit_test::Suite
             auto const rs =
                 env.rpc("json", "channel_authorize", args.toStyledString())[jss::result];
             auto const error = apiVersion < 2u ? "invalidParams" : "badKeyType";
+            auto const errorCode = apiVersion < 2u ? RpcInvalidParams : RpcBadKeyType;
+            auto const errorMessage =
+                apiVersion < 2u ? "Invalid field 'key_type'." : "Bad key type.";
             BEAST_EXPECT(rs[jss::error] == error);
+            BEAST_EXPECT(rs[jss::error_code] == errorCode);
+            BEAST_EXPECT(rs[jss::error_message] == errorMessage);
         });
     }
 
@@ -1339,22 +1423,40 @@ struct PayChan_test : public beast::unit_test::Suite
                 auto const pkAsHex = sliceToHex(pk.slice());
                 auto rv = env.rpc("channel_verify", pkAsHex, chan1Str, "1000x", sig);
                 BEAST_EXPECT(rv[jss::error] == "channelAmtMalformed");
+                BEAST_EXPECT(rv[jss::error_code] == RpcChannelAmtMalformed);
+                BEAST_EXPECT(rv[jss::error_message] == "Payment channel amount is malformed.");
                 rv = env.rpc("channel_verify", pkAsHex, chan1Str, "1000 ", sig);
                 BEAST_EXPECT(rv[jss::error] == "channelAmtMalformed");
+                BEAST_EXPECT(rv[jss::error_code] == RpcChannelAmtMalformed);
+                BEAST_EXPECT(rv[jss::error_message] == "Payment channel amount is malformed.");
                 rv = env.rpc("channel_verify", pkAsHex, chan1Str, "x1000", sig);
                 BEAST_EXPECT(rv[jss::error] == "channelAmtMalformed");
+                BEAST_EXPECT(rv[jss::error_code] == RpcChannelAmtMalformed);
+                BEAST_EXPECT(rv[jss::error_message] == "Payment channel amount is malformed.");
                 rv = env.rpc("channel_verify", pkAsHex, chan1Str, "x", sig);
                 BEAST_EXPECT(rv[jss::error] == "channelAmtMalformed");
+                BEAST_EXPECT(rv[jss::error_code] == RpcChannelAmtMalformed);
+                BEAST_EXPECT(rv[jss::error_message] == "Payment channel amount is malformed.");
                 rv = env.rpc("channel_verify", pkAsHex, chan1Str, " ", sig);
                 BEAST_EXPECT(rv[jss::error] == "channelAmtMalformed");
+                BEAST_EXPECT(rv[jss::error_code] == RpcChannelAmtMalformed);
+                BEAST_EXPECT(rv[jss::error_message] == "Payment channel amount is malformed.");
                 rv = env.rpc("channel_verify", pkAsHex, chan1Str, "1000 1000", sig);
                 BEAST_EXPECT(rv[jss::error] == "channelAmtMalformed");
+                BEAST_EXPECT(rv[jss::error_code] == RpcChannelAmtMalformed);
+                BEAST_EXPECT(rv[jss::error_message] == "Payment channel amount is malformed.");
                 rv = env.rpc("channel_verify", pkAsHex, chan1Str, "1,000", sig);
                 BEAST_EXPECT(rv[jss::error] == "channelAmtMalformed");
+                BEAST_EXPECT(rv[jss::error_code] == RpcChannelAmtMalformed);
+                BEAST_EXPECT(rv[jss::error_message] == "Payment channel amount is malformed.");
                 rv = env.rpc("channel_verify", pkAsHex, chan1Str, " 1000", sig);
                 BEAST_EXPECT(rv[jss::error] == "channelAmtMalformed");
+                BEAST_EXPECT(rv[jss::error_code] == RpcChannelAmtMalformed);
+                BEAST_EXPECT(rv[jss::error_message] == "Payment channel amount is malformed.");
                 rv = env.rpc("channel_verify", pkAsHex, chan1Str, "", sig);
                 BEAST_EXPECT(rv[jss::error] == "channelAmtMalformed");
+                BEAST_EXPECT(rv[jss::error_code] == RpcChannelAmtMalformed);
+                BEAST_EXPECT(rv[jss::error_message] == "Payment channel amount is malformed.");
             }
             {
                 // malformed channel
@@ -1363,22 +1465,34 @@ struct PayChan_test : public beast::unit_test::Suite
                 chan1StrBad.pop_back();
                 auto rv = env.rpc("channel_verify", pkAsHex, chan1StrBad, "1000", sig);
                 BEAST_EXPECT(rv[jss::error] == "channelMalformed");
+                BEAST_EXPECT(rv[jss::error_code] == RpcChannelMalformed);
+                BEAST_EXPECT(rv[jss::error_message] == "Payment channel is malformed.");
                 rv = env.rpc("channel_authorize", "alice", chan1StrBad, "1000");
                 BEAST_EXPECT(rv[jss::error] == "channelMalformed");
+                BEAST_EXPECT(rv[jss::error_code] == RpcChannelMalformed);
+                BEAST_EXPECT(rv[jss::error_message] == "Payment channel is malformed.");
 
                 chan1StrBad = chan1Str;
                 chan1StrBad.push_back('0');
                 rv = env.rpc("channel_verify", pkAsHex, chan1StrBad, "1000", sig);
                 BEAST_EXPECT(rv[jss::error] == "channelMalformed");
+                BEAST_EXPECT(rv[jss::error_code] == RpcChannelMalformed);
+                BEAST_EXPECT(rv[jss::error_message] == "Payment channel is malformed.");
                 rv = env.rpc("channel_authorize", "alice", chan1StrBad, "1000");
                 BEAST_EXPECT(rv[jss::error] == "channelMalformed");
+                BEAST_EXPECT(rv[jss::error_code] == RpcChannelMalformed);
+                BEAST_EXPECT(rv[jss::error_message] == "Payment channel is malformed.");
 
                 chan1StrBad = chan1Str;
                 chan1StrBad.back() = 'x';
                 rv = env.rpc("channel_verify", pkAsHex, chan1StrBad, "1000", sig);
                 BEAST_EXPECT(rv[jss::error] == "channelMalformed");
+                BEAST_EXPECT(rv[jss::error_code] == RpcChannelMalformed);
+                BEAST_EXPECT(rv[jss::error_message] == "Payment channel is malformed.");
                 rv = env.rpc("channel_authorize", "alice", chan1StrBad, "1000");
                 BEAST_EXPECT(rv[jss::error] == "channelMalformed");
+                BEAST_EXPECT(rv[jss::error_code] == RpcChannelMalformed);
+                BEAST_EXPECT(rv[jss::error_message] == "Payment channel is malformed.");
             }
             {
                 // channel_id is not a string.
@@ -1391,6 +1505,8 @@ struct PayChan_test : public beast::unit_test::Suite
                 auto const ra =
                     env.rpc("json", "channel_authorize", args.toStyledString())[jss::result];
                 BEAST_EXPECT(ra[jss::error] == "invalidParams");
+                BEAST_EXPECT(ra[jss::error_code] == RpcInvalidParams);
+                BEAST_EXPECT(ra[jss::error_message] == "Invalid parameters.");
             }
             {
                 // channel_id is not a string.
@@ -1403,6 +1519,8 @@ struct PayChan_test : public beast::unit_test::Suite
                 auto const rv =
                     env.rpc("json", "channel_verify", args.toStyledString())[jss::result];
                 BEAST_EXPECT(rv[jss::error] == "invalidParams");
+                BEAST_EXPECT(rv[jss::error_code] == RpcInvalidParams);
+                BEAST_EXPECT(rv[jss::error_message] == "Invalid parameters.");
             }
             {
                 // give an ill formed base 58 public key
@@ -1461,6 +1579,8 @@ struct PayChan_test : public beast::unit_test::Suite
             // Try to authorize using an unknown key type, except an error:
             auto const rs1 = env.rpc("channel_authorize", "charlie", "nyx", chan, "1000");
             BEAST_EXPECT(rs1[jss::error] == "badKeyType");
+            BEAST_EXPECT(rs1[jss::error_code] == RpcBadKeyType);
+            BEAST_EXPECT(rs1[jss::error_message] == "Bad key type.");
 
             // Try to authorize using secp256k1; the authorization _should_
             // succeed but the verification should fail:
@@ -1486,10 +1606,16 @@ struct PayChan_test : public beast::unit_test::Suite
             // send malformed amounts rpc requests
             auto rs = env.rpc("channel_authorize", "alice", chan1Str, "1000x");
             BEAST_EXPECT(rs[jss::error] == "channelAmtMalformed");
+            BEAST_EXPECT(rs[jss::error_code] == RpcChannelAmtMalformed);
+            BEAST_EXPECT(rs[jss::error_message] == "Payment channel amount is malformed.");
             rs = env.rpc("channel_authorize", "alice", chan1Str, "x1000");
             BEAST_EXPECT(rs[jss::error] == "channelAmtMalformed");
+            BEAST_EXPECT(rs[jss::error_code] == RpcChannelAmtMalformed);
+            BEAST_EXPECT(rs[jss::error_message] == "Payment channel amount is malformed.");
             rs = env.rpc("channel_authorize", "alice", chan1Str, "x");
             BEAST_EXPECT(rs[jss::error] == "channelAmtMalformed");
+            BEAST_EXPECT(rs[jss::error_code] == RpcChannelAmtMalformed);
+            BEAST_EXPECT(rs[jss::error_message] == "Payment channel amount is malformed.");
             {
                 // Missing channel_id
                 json::Value args{json::ValueType::Object};
@@ -1498,6 +1624,8 @@ struct PayChan_test : public beast::unit_test::Suite
                 args[jss::passphrase] = "passphrase_can_be_anything";
                 rs = env.rpc("json", "channel_authorize", args.toStyledString())[jss::result];
                 BEAST_EXPECT(rs[jss::error] == "invalidParams");
+                BEAST_EXPECT(rs[jss::error_code] == RpcInvalidParams);
+                BEAST_EXPECT(rs[jss::error_message] == "Missing field 'channel_id'.");
             }
             {
                 // Missing amount
@@ -1507,6 +1635,8 @@ struct PayChan_test : public beast::unit_test::Suite
                 args[jss::passphrase] = "passphrase_can_be_anything";
                 rs = env.rpc("json", "channel_authorize", args.toStyledString())[jss::result];
                 BEAST_EXPECT(rs[jss::error] == "invalidParams");
+                BEAST_EXPECT(rs[jss::error_code] == RpcInvalidParams);
+                BEAST_EXPECT(rs[jss::error_message] == "Missing field 'amount'.");
             }
             {
                 // Missing key_type and no secret.
@@ -1516,6 +1646,8 @@ struct PayChan_test : public beast::unit_test::Suite
                 args[jss::passphrase] = "passphrase_can_be_anything";
                 rs = env.rpc("json", "channel_authorize", args.toStyledString())[jss::result];
                 BEAST_EXPECT(rs[jss::error] == "invalidParams");
+                BEAST_EXPECT(rs[jss::error_code] == RpcInvalidParams);
+                BEAST_EXPECT(rs[jss::error_message] == "Missing field 'secret'.");
             }
             {
                 // Both passphrase and seed specified.
@@ -1527,6 +1659,11 @@ struct PayChan_test : public beast::unit_test::Suite
                 args[jss::seed] = "seed can be anything";
                 rs = env.rpc("json", "channel_authorize", args.toStyledString())[jss::result];
                 BEAST_EXPECT(rs[jss::error] == "invalidParams");
+                BEAST_EXPECT(rs[jss::error_code] == RpcInvalidParams);
+                BEAST_EXPECT(
+                    rs[jss::error_message] ==
+                    "Exactly one of the following must be specified: passphrase, secret, seed or "
+                    "seed_hex");
             }
             {
                 // channel_id is not exact hex.
@@ -1537,6 +1674,8 @@ struct PayChan_test : public beast::unit_test::Suite
                 args[jss::passphrase] = "passphrase_can_be_anything";
                 rs = env.rpc("json", "channel_authorize", args.toStyledString())[jss::result];
                 BEAST_EXPECT(rs[jss::error] == "channelMalformed");
+                BEAST_EXPECT(rs[jss::error_code] == RpcChannelMalformed);
+                BEAST_EXPECT(rs[jss::error_message] == "Payment channel is malformed.");
             }
             {
                 // amount is not a string
@@ -1547,6 +1686,8 @@ struct PayChan_test : public beast::unit_test::Suite
                 args[jss::passphrase] = "passphrase_can_be_anything";
                 rs = env.rpc("json", "channel_authorize", args.toStyledString())[jss::result];
                 BEAST_EXPECT(rs[jss::error] == "channelAmtMalformed");
+                BEAST_EXPECT(rs[jss::error_code] == RpcChannelAmtMalformed);
+                BEAST_EXPECT(rs[jss::error_message] == "Payment channel amount is malformed.");
             }
             {
                 // Amount is not a decimal string.
@@ -1557,6 +1698,8 @@ struct PayChan_test : public beast::unit_test::Suite
                 args[jss::passphrase] = "passphrase_can_be_anything";
                 rs = env.rpc("json", "channel_authorize", args.toStyledString())[jss::result];
                 BEAST_EXPECT(rs[jss::error] == "channelAmtMalformed");
+                BEAST_EXPECT(rs[jss::error_code] == RpcChannelAmtMalformed);
+                BEAST_EXPECT(rs[jss::error_message] == "Payment channel amount is malformed.");
             }
         }
     }
@@ -1807,6 +1950,8 @@ struct PayChan_test : public beast::unit_test::Suite
         )*";
             auto const r = env.rpc("json", "channel_verify", txn);
             BEAST_EXPECT(r["result"]["error"] == "publicMalformed");
+            BEAST_EXPECT(r["result"]["error_code"] == RpcPublicMalformed);
+            BEAST_EXPECT(r["result"]["error_message"] == "Public key is malformed.");
         }
     }
 

src/test/app/ReducedOffer_test.cpp

@@ -13,6 +13,7 @@
 #include <xrpl/beast/unit_test/suite.h>
 #include <xrpl/json/json_value.h>
 #include <xrpl/json/to_string.h>
+#include <xrpl/protocol/ErrorCodes.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/Quality.h>
 #include <xrpl/protocol/SField.h>
@@ -42,8 +43,9 @@ class ReducedOffer_test : public beast::unit_test::Suite
     {
         json::Value ledgerOffer = ledgerEntryOffer(env, acct, offerSeq);
         return !(
-            ledgerOffer.isMember(jss::error) &&
-            ledgerOffer[jss::error].asString() == "entryNotFound");
+            ledgerOffer[jss::error].asString() == "entryNotFound" &&
+            ledgerOffer[jss::error_code] == RpcEntryNotFound &&
+            ledgerOffer[jss::error_message] == "Entry not found.");
     }
 
     // Common code to clean up unneeded offers.

src/test/app/SHAMapStore_test.cpp

@@ -302,10 +302,14 @@ class SHAMapStore_test : public beast::unit_test::Suite
     }
 
     static bool
-    bad(json::Value const& json, ErrorCodeI error = RpcLgrNotFound)
+    bad(json::Value const& json,
+        std::string const& token,
+        ErrorCodeI error,
+        std::string const& message)
     {
-        return json.isMember(jss::result) && rpc::containsError(json[jss::result]) &&
-            json[jss::result][jss::error_code] == error;
+        return json.isMember(jss::result) && json[jss::result][jss::error] == token &&
+            json[jss::result][jss::error_code] == error &&
+            json[jss::result][jss::error_message] == message;
     }
 
     std::string
@@ -883,7 +887,7 @@ public:
         std::map<std::uint32_t, json::Value const> ledgers;
 
         auto ledgerTmp = env.rpc("ledger", "0");
-        BEAST_EXPECT(bad(ledgerTmp));
+        BEAST_EXPECT(bad(ledgerTmp, "lgrNotFound", RpcLgrNotFound, "ledgerNotFound"));
 
         ledgers.emplace(1, env.rpc("ledger", "1"));
         BEAST_EXPECT(goodLedger(env, ledgers[1], "1"));
@@ -895,10 +899,10 @@ public:
         BEAST_EXPECT(goodLedger(env, ledgerTmp, "3"));
 
         ledgerTmp = env.rpc("ledger", "4");
-        BEAST_EXPECT(bad(ledgerTmp));
+        BEAST_EXPECT(bad(ledgerTmp, "lgrNotFound", RpcLgrNotFound, "ledgerNotFound"));
 
         ledgerTmp = env.rpc("ledger", "100");
-        BEAST_EXPECT(bad(ledgerTmp));
+        BEAST_EXPECT(bad(ledgerTmp, "lgrNotFound", RpcLgrNotFound, "ledgerNotFound"));
 
         auto const firstSeq = waitForReady(env);
         auto lastRotated = firstSeq - 1;
@@ -987,7 +991,7 @@ public:
         // Because advisory_delete is unset,
         // "can_delete" is disabled.
         auto const canDelete = env.rpc("can_delete");
-        BEAST_EXPECT(bad(canDelete, RpcNotEnabled));
+        BEAST_EXPECT(bad(canDelete, "notEnabled", RpcNotEnabled, "Not enabled in configuration."));
 
         // Close ledgers without triggering a rotate
         for (; ledgerSeq < lastRotated + kDeleteInterval; ++ledgerSeq)

src/test/app/Sponsor_test.cpp

@@ -59,6 +59,7 @@
 #include <xrpl/tx/apply.h>
 #include <xrpl/tx/applySteps.h>
 
+#include <cstddef>
 #include <cstdint>
 #include <functional>
 #include <limits>
@@ -3550,6 +3551,101 @@ public:
             BEAST_EXPECT(sponsoringOwnerCount(env, sponsor2) == 0);
         }
 
+        {
+            // Bytecode Escrow: its reserve scales with the Bytecode size, so
+            // every leg of a sponsorship has to move the whole weight.
+            auto env = Env{*this, testableAmendments()};
+
+            env.fund(XRP(1000000), alice, bob, sponsor, sponsor2);
+            env.close();
+
+            auto const seq = env.seq(alice);
+            env(escrow::create(alice, bob, XRP(100)),
+                escrow::kCondition(escrow::kCb1),
+                escrow::kCancelTime(env.now() + 100s));
+            env.close();
+
+            auto const escrowKeylet = keylet::escrow(alice, SeqProxy::rawSequence(seq));
+            std::size_t const bytecodeSize = 1200;
+            std::uint32_t const bytecodeWeight = 3;  // ceil(1200 / 500)
+
+            if (!cosigning)
+            {
+                env(sponsor::set_reserve(sponsor, 0, bytecodeWeight), sponsor::SponseeAcc(alice));
+                env(sponsor::set_reserve(sponsor2, 0, bytecodeWeight), sponsor::SponseeAcc(alice));
+                env.close();
+            }
+
+            // EscrowCreate's preclaim runs the WASM preflight, so a real
+            // 1200-byte contract cannot be assembled from here; the Bytecode
+            // field is injected directly and the owner's OwnerCount restored
+            // to the weight such a create would have charged.
+            env.app().getOpenLedger().modify([&](OpenView& view, beast::Journal) -> bool {
+                auto const existing = view.read(escrowKeylet);
+                if (!existing)
+                {
+                    return false;
+                }
+                auto const escrowSle = std::make_shared<SLE>(*existing);
+                auto const account = std::make_shared<SLE>(*view.read(keylet::account(alice.id())));
+                escrowSle->setFieldVL(sfBytecode, Blob(bytecodeSize, 0x00));
+                account->setFieldU32(sfOwnerCount, bytecodeWeight);
+                view.rawReplace(escrowSle);
+                view.rawReplace(account);
+                return true;
+            });
+            BEAST_EXPECT(ownerCount(env, alice) == bytecodeWeight);
+
+            std::optional<Sig> const sponsorSig =
+                cosigning ? std::optional<Sig>(Sig(sfSponsorSignature, sponsor)) : std::nullopt;
+            std::optional<Sig> const sponsor2Sig =
+                cosigning ? std::optional<Sig>(Sig(sfSponsorSignature, sponsor2)) : std::nullopt;
+
+            // create sponsor: charges the whole bytecode weight, not 1
+            if (sponsorSig)
+            {
+                env(sponsor::transfer(alice, tfSponsorshipCreate, escrowKeylet.key),
+                    sponsor::As(sponsor, spfSponsorReserve),
+                    *sponsorSig);
+            }
+            else
+            {
+                env(sponsor::transfer(alice, tfSponsorshipCreate, escrowKeylet.key),
+                    sponsor::As(sponsor, spfSponsorReserve));
+            }
+
+            BEAST_EXPECT(sponsoredOwnerCount(env, alice) == bytecodeWeight);
+            BEAST_EXPECT(sponsoringOwnerCount(env, sponsor) == bytecodeWeight);
+            BEAST_EXPECT(env.le(escrowKeylet)->getAccountID(sfSponsor) == sponsor.id());
+
+            // transfer sponsor: moves the whole weight between the two sponsors
+            if (sponsor2Sig)
+            {
+                env(sponsor::transfer(alice, tfSponsorshipReassign, escrowKeylet.key),
+                    sponsor::As(sponsor2, spfSponsorReserve),
+                    *sponsor2Sig);
+            }
+            else
+            {
+                env(sponsor::transfer(alice, tfSponsorshipReassign, escrowKeylet.key),
+                    sponsor::As(sponsor2, spfSponsorReserve));
+            }
+
+            BEAST_EXPECT(sponsoredOwnerCount(env, alice) == bytecodeWeight);
+            BEAST_EXPECT(sponsoringOwnerCount(env, sponsor) == 0);
+            BEAST_EXPECT(sponsoringOwnerCount(env, sponsor2) == bytecodeWeight);
+            BEAST_EXPECT(env.le(escrowKeylet)->getAccountID(sfSponsor) == sponsor2.id());
+
+            // end sponsor: hands the whole weight back to the owner
+            env(sponsor::transfer(alice, tfSponsorshipEnd, escrowKeylet.key));
+
+            BEAST_EXPECT(ownerCount(env, alice) == bytecodeWeight);
+            BEAST_EXPECT(sponsoredOwnerCount(env, alice) == 0);
+            BEAST_EXPECT(sponsoringOwnerCount(env, sponsor) == 0);
+            BEAST_EXPECT(sponsoringOwnerCount(env, sponsor2) == 0);
+            BEAST_EXPECT(!env.le(escrowKeylet)->isFieldPresent(sfSponsor));
+        }
+
         Account const gw("gw");
         auto const usd = gw["usd"];
         {
@@ -4405,6 +4501,89 @@ public:
             BEAST_EXPECT(!sle->isFieldPresent(sfRemainingOwnerCount));
     }
 
+    // An escrow carrying Bytecode costs one owner count per 500 bytes, so
+    // sponsoring one must move that full weight rather than a single unit.
+    void
+    testBytecodeEscrowReserve()
+    {
+        testcase("Bytecode escrow sponsorship reserve");
+        using namespace test::jtx;
+        using namespace std::chrono_literals;
+
+        auto const alice = Account{"alice"};
+        auto const bob = Account{"bob"};
+        auto const sponsor = Account{"sponsor"};
+
+        auto env = Env{*this, testableAmendments()};
+        env.fund(XRP(1000000), alice, bob, sponsor);
+        env.close();
+
+        auto const seq = env.seq(alice);
+        env(escrow::create(alice, bob, XRP(100)),
+            escrow::kCondition(escrow::kCb1),
+            escrow::kCancelTime(env.now() + 100s));
+        env.close();
+
+        auto const escrowKeylet = keylet::escrow(alice, SeqProxy::rawSequence(seq));
+        auto const sponsorKeylet = keylet::sponsorship(sponsor.id(), alice.id());
+        std::size_t const bytecodeSize = 1200;
+        std::uint32_t const bytecodeWeight = 3;  // ceil(1200 / 500)
+        BEAST_EXPECT(ownerCount(env, alice) == 1);
+
+        // Pre-fund exactly the bytecode weight
+        env(sponsor::set_reserve(sponsor, 0, bytecodeWeight), sponsor::SponseeAcc(alice));
+        env.close();
+        if (auto const sle = env.le(sponsorKeylet); BEAST_EXPECT(sle))
+        {
+            BEAST_EXPECT(sle->getFieldU32(sfRemainingOwnerCount) == bytecodeWeight);
+        }
+
+        // Synthesize a bytecode escrow. EscrowCreate's preclaim runs the WASM
+        // preflight, so a real 1200-byte contract cannot be assembled from
+        // here; the Bytecode field is injected directly and the owner's
+        // OwnerCount restored to the weight such a create would have charged.
+        env.app().getOpenLedger().modify([&](OpenView& view, beast::Journal) -> bool {
+            auto const existing = view.read(escrowKeylet);
+            if (!existing)
+            {
+                return false;
+            }
+            auto const escrowSle = std::make_shared<SLE>(*existing);
+            auto const account = std::make_shared<SLE>(*view.read(keylet::account(alice.id())));
+            escrowSle->setFieldVL(sfBytecode, Blob(bytecodeSize, 0x00));
+            account->setFieldU32(sfOwnerCount, bytecodeWeight);
+            view.rawReplace(escrowSle);
+            view.rawReplace(account);
+            return true;
+        });
+        BEAST_EXPECT(ownerCount(env, alice) == bytecodeWeight);
+
+        // Create must charge the full bytecode weight (3), not 1: counting the
+        // escrow as a single unit would leave 2 pre-funded units unspent.
+        env(sponsor::transfer(alice, tfSponsorshipCreate, escrowKeylet.key),
+            sponsor::As(sponsor, spfSponsorReserve));
+
+        BEAST_EXPECT(sponsoredOwnerCount(env, alice) == bytecodeWeight);
+        BEAST_EXPECT(sponsoringOwnerCount(env, sponsor) == bytecodeWeight);
+        // All pre-funded units consumed (drained to absent).
+        if (auto const sle = env.le(sponsorKeylet); BEAST_EXPECT(sle))
+        {
+            BEAST_EXPECT(!sle->isFieldPresent(sfRemainingOwnerCount));
+        }
+
+        // End hands the same weight back; create bumped by the same amount, so
+        // the counters return to 0 (counting 1 here would underflow).
+        env(sponsor::transfer(alice, tfSponsorshipEnd, escrowKeylet.key));
+
+        BEAST_EXPECT(ownerCount(env, alice) == bytecodeWeight);
+        BEAST_EXPECT(sponsoredOwnerCount(env, alice) == 0);
+        BEAST_EXPECT(sponsoringOwnerCount(env, sponsor) == 0);
+        if (auto const sle = env.le(escrowKeylet); BEAST_EXPECT(sle))
+        {
+            BEAST_EXPECT(!sle->isFieldPresent(sfSponsor));
+        }
+    }
+
     void
     testSponsoredTrustLineNoFreeReserve()
     {
@@ -5790,6 +5969,7 @@ protected:
         testTransferSponsor(jtx::testableAmendments());
         testTransferSponsor(jtx::testableAmendments() - fixCleanup3_4_0);
         testLegacySignerListReserve();
+        testBytecodeEscrowReserve();
         testSponsorFee();
         testSponsorAccount();
 

src/test/app/TransactionProposalCancel_test.cpp

@@ -20,6 +20,7 @@
 #include <xrpl/beast/unit_test/suite.h>
 #include <xrpl/json/json_value.h>
 #include <xrpl/json/to_string.h>
+#include <xrpl/protocol/ErrorCodes.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/Indexes.h>
 #include <xrpl/protocol/Protocol.h>
@@ -215,8 +216,9 @@ struct TransactionProposalCancel_test : public beast::unit_test::Suite
     }
 
     // The target account may refuse any proposal made for it, at any point in
-    // its lifecycle, without owning the object: anyone can create a proposal
-    // against any account and tie up one of its tickets (On-Chain Cosigner spec §7.2).
+    // its lifecycle, without owning the object: any of its signers, an
+    // authorized delegate, or that delegate's signers can create one and tie
+    // up one of its tickets (XLS-0103 §7.2).
     void
     testTargetCancel(FeatureBitset features)
     {
@@ -683,6 +685,25 @@ struct TransactionProposalCancel_test : public beast::unit_test::Suite
             BEAST_EXPECT(env.le(keylet::txProposal(proposalID)));
             BEAST_EXPECT(ownerCount(env, alice) == proposal::kProposalOwnerCount);
         }
+
+        // Paying with a ticket changes none of that. The failed cancel still
+        // consumes carol's ticket, and nothing else moves: the proposal and
+        // its reserve stay as they were.
+        {
+            uint256 const proposalID = makeProposal(env, alice, target, bob);
+            std::uint32_t const cancelTicket = proposal::createTicket(env, carol);
+            auto const aliceOwnerCount = ownerCount(env, alice);
+
+            env(proposal::cancel(carol, proposalID),
+                ticket::Use(cancelTicket),
+                Ter(tecNO_PERMISSION));
+            env.close();
+
+            BEAST_EXPECT(env.le(keylet::txProposal(proposalID)));
+            BEAST_EXPECT(!env.le(keylet::ticket(carol.id(), SeqProxy::rawTicket(cancelTicket))));
+            BEAST_EXPECT(ownerCount(env, alice) == aliceOwnerCount);
+            BEAST_EXPECT(ownerCount(env, carol) == 0);
+        }
     }
 
     // A Cancel works as an inner Batch transaction, where each inner runs its
@@ -1012,15 +1033,25 @@ struct TransactionProposalCancel_test : public beast::unit_test::Suite
         {
             json::Value noTicket;
             noTicket[jss::account] = target.human();
-            BEAST_EXPECT(ledgerEntry(noTicket)[jss::error] == "malformedRequest");
+            auto const noTicketResult = ledgerEntry(noTicket);
+            BEAST_EXPECT(noTicketResult[jss::error] == "malformedRequest");
+            BEAST_EXPECT(noTicketResult[jss::error_code] == RpcInvalidParams);
+            BEAST_EXPECT(noTicketResult[jss::error_message] == "Missing field 'ticket_seq'.");
 
             json::Value noAccount;
             noAccount[jss::ticket_seq] = ticketSeq;
-            BEAST_EXPECT(ledgerEntry(noAccount)[jss::error] == "malformedRequest");
+            auto const noAccountResult = ledgerEntry(noAccount);
+            BEAST_EXPECT(noAccountResult[jss::error] == "malformedRequest");
+            BEAST_EXPECT(noAccountResult[jss::error_code] == RpcInvalidParams);
+            BEAST_EXPECT(noAccountResult[jss::error_message] == "Missing field 'account'.");
 
             json::Value badAccount = byPair;
             badAccount[jss::account] = "not an account";
-            BEAST_EXPECT(ledgerEntry(badAccount)[jss::error] == "malformedAddress");
+            auto const badAccountResult = ledgerEntry(badAccount);
+            BEAST_EXPECT(badAccountResult[jss::error] == "malformedAddress");
+            BEAST_EXPECT(badAccountResult[jss::error_code] == RpcInvalidParams);
+            BEAST_EXPECT(
+                badAccountResult[jss::error_message] == "Invalid field 'account', not AccountID.");
         }
 
         // Listed for the proposer, who owns it, and not for the target.
@@ -1037,6 +1068,8 @@ struct TransactionProposalCancel_test : public beast::unit_test::Suite
         {
             auto const jrr = ledgerEntry(byPair);
             BEAST_EXPECT(jrr[jss::error] == "entryNotFound");
+            BEAST_EXPECT(jrr[jss::error_code] == RpcEntryNotFound);
+            BEAST_EXPECT(jrr[jss::error_message] == "Entry not found.");
             BEAST_EXPECT(!jrr.isMember(jss::node));
             BEAST_EXPECT(jrr[jss::index] == to_string(proposalID));
         }

src/test/app/TransactionProposalCreate_test.cpp

@@ -1357,6 +1357,51 @@ struct TransactionProposalCreate_test : public beast::unit_test::Suite
         env.close();
     }
 
+    // A proposer may pay for the Create with one of its own Tickets. The
+    // Ticket's reserve goes as the proposal's arrives, so the proposer's owner
+    // count moves by the difference.
+    void
+    testTicketedCreate(FeatureBitset features)
+    {
+        testcase("create paid for with the proposer's own ticket");
+
+        using namespace jtx;
+        using namespace std::chrono_literals;
+
+        Env env{*this, features};
+
+        Account const alice{"alice"};    // the proposer
+        Account const target{"target"};  // the account the proposal is for
+        Account const bob{"bob"};
+        env.fund(XRP(10000), alice, target, bob);
+        env.close();
+        proposal::authorizeProposer(env, target, alice);
+
+        std::uint32_t const targetTicketSeq = proposal::createTicket(env, target);
+        std::uint32_t const aliceTicketSeq = proposal::createTicket(env, alice);
+        std::uint32_t const aliceSeq = env.seq(alice);
+        std::uint32_t const targetOwnerCount = ownerCount(env, target);
+        BEAST_EXPECT(ownerCount(env, alice) == 1);
+
+        // The proposal's reserve lands on alice less the Ticket she paid with,
+        // and her Sequence is untouched.
+        env(proposal::create(
+                alice,
+                proposal::unsignedPayload(env, pay(target, bob, XRP(1)), targetTicketSeq),
+                proposal::expiration(env, 100s)),
+            ticket::Use(aliceTicketSeq),
+            proposal::verify::create());
+        env.close();
+
+        BEAST_EXPECT(proposal::entry(env, target, targetTicketSeq));
+        BEAST_EXPECT(!env.le(keylet::ticket(alice.id(), SeqProxy::rawTicket(aliceTicketSeq))));
+        BEAST_EXPECT(env.seq(alice) == aliceSeq);
+        BEAST_EXPECT(ownerCount(env, alice) == proposal::kProposalOwnerCount);
+
+        // The target's Ticket, the one the proposal is keyed to, stays.
+        BEAST_EXPECT(ownerCount(env, target) == targetOwnerCount);
+    }
+
     // The proposal's reserve can instead be sponsored: the reserve is charged
     // to the sponsor's account, and the ledger object records the sponsor, the
     // same as any other reserve-sponsorable object (TransactionProposalCreate
@@ -1728,6 +1773,7 @@ struct TransactionProposalCreate_test : public beast::unit_test::Suite
         testOtherTransactionTypes(all);
         testAuxiliaryCoSignatureTypes(all);
         testReserve(all);
+        testTicketedCreate(all);
         testSponsoredReserve(all);
         testSponsorshipTransfer(all);
         testFeeSponsored(all);

src/test/app/TrustAndBalance_test.cpp

@@ -14,6 +14,7 @@
 #include <xrpl/basics/strHex.h>
 #include <xrpl/beast/unit_test/suite.h>
 #include <xrpl/json/json_value.h>
+#include <xrpl/protocol/ErrorCodes.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/SField.h>
 #include <xrpl/protocol/TER.h>
@@ -66,6 +67,8 @@ class TrustAndBalance_test : public beast::unit_test::Suite
         // reflects this
         auto jrr = ledgerEntryState(env, gw, alice, "USD");
         BEAST_EXPECT(jrr[jss::error] == "entryNotFound");
+        BEAST_EXPECT(jrr[jss::error_code] == RpcEntryNotFound);
+        BEAST_EXPECT(jrr[jss::error_message] == "Entry not found.");
 
         // now create a credit limit
         env(trust(alice, gw["USD"](800)));
@@ -100,6 +103,8 @@ class TrustAndBalance_test : public beast::unit_test::Suite
         // ensure line is deleted
         jrr = ledgerEntryState(env, gw, alice, "USD");
         BEAST_EXPECT(jrr[jss::error] == "entryNotFound");
+        BEAST_EXPECT(jrr[jss::error_code] == RpcEntryNotFound);
+        BEAST_EXPECT(jrr[jss::error_message] == "Entry not found.");
 
         // TODO Check in both owner books.
 

src/test/app/TxQ_test.cpp

@@ -3231,7 +3231,9 @@ public:
 
         {
             auto const info = env.rpc("json", "account_info", to_string(prevLedgerWithQueue));
-            BEAST_EXPECT(info.isMember(jss::result) && rpc::containsError(info[jss::result]));
+            BEAST_EXPECT(info[jss::result][jss::error] == "invalidParams");
+            BEAST_EXPECT(info[jss::result][jss::error_code] == RpcInvalidParams);
+            BEAST_EXPECT(info[jss::result][jss::error_message] == "Invalid parameters.");
         }
 
         env.close();

src/test/app/invariants/InvariantsMisc_test.cpp

@@ -4,6 +4,7 @@
 #include <test/jtx/Env.h>
 #include <test/jtx/TestHelpers.h>
 #include <test/jtx/amount.h>
+#include <test/jtx/escrow.h>
 #include <test/jtx/pay.h>
 #include <test/jtx/token.h>
 #include <test/jtx/trust.h>
@@ -1330,6 +1331,51 @@ class InvariantsMisc_test : public InvariantsBase
                     env(check::create(a1, a2, XRP(1)));
                     return true;
                 });
+
+            // An escrow's owner count scales with its Bytecode size, so
+            // sponsoring one has to move that whole weight. Counting it as a
+            // single unit leaves the sponsored counters short of the object's
+            // real weight, which is what this check exists to catch.
+            UInt256 escrowID;
+
+            doInvariantCheck(
+                {{expectMessage}},
+                [&](Account const& a1, Account const& a2, ApplyContext& ac) {
+                    auto const escrow = ac.view().peek(keylet::unchecked(escrowID));
+                    if (!escrow)
+                    {
+                        return false;
+                    }
+                    // ceil(1200 / 500) == 3 owner counts
+                    escrow->setFieldVL(sfBytecode, Blob(1200, 0x00));
+                    escrow->setAccountID(sfSponsor, a2.id());
+                    ac.view().update(escrow);
+
+                    // Move the counters by a single unit, as a sponsorship
+                    // blind to the Bytecode weight would.
+                    auto const sle1 = ac.view().peek(keylet::account(a1.id()));
+                    auto const sle2 = ac.view().peek(keylet::account(a2.id()));
+                    if (!sle1 || !sle2)
+                    {
+                        return false;
+                    }
+                    sle1->setFieldU32(sfSponsoredOwnerCount, 1);
+                    sle2->setFieldU32(sfSponsoringOwnerCount, 1);
+                    ac.view().update(sle1);
+                    ac.view().update(sle2);
+                    return true;
+                },
+                XRPAmount{},
+                STTx{ttACCOUNT_SET, [](STObject&) {}},
+                {tecINVARIANT_FAILED, tefINVARIANT_FAILED},
+                [&escrowID](Account const& a1, Account const& a2, Env& env) {
+                    using namespace std::chrono_literals;
+                    escrowID = keylet::escrow(a1.id(), SeqProxy::rawSequence(env.seq(a1))).key;
+                    env(escrow::create(a1, a2, XRP(1)),
+                        escrow::kCondition(escrow::kCb1),
+                        escrow::kCancelTime(env.now() + 100s));
+                    return true;
+                });
         }
 
         {

src/test/app/invariants/InvariantsTransactionProposal_test.cpp

@@ -0,0 +1,549 @@
+#include <test/app/invariants/InvariantsBase.h>
+#include <test/jtx/Account.h>
+#include <test/jtx/Env.h>
+#include <test/jtx/amount.h>
+#include <test/jtx/pay.h>
+#include <test/jtx/proposal.h>
+#include <test/jtx/utility.h>
+
+#include <xrpl/beast/unit_test/suite.h>
+#include <xrpl/beast/utility/Zero.h>
+#include <xrpl/ledger/ApplyView.h>
+#include <xrpl/ledger/helpers/ProposalHelpers.h>
+#include <xrpl/protocol/AccountID.h>
+#include <xrpl/protocol/Indexes.h>
+#include <xrpl/protocol/Keylet.h>
+#include <xrpl/protocol/Protocol.h>
+#include <xrpl/protocol/SField.h>
+#include <xrpl/protocol/STArray.h>
+#include <xrpl/protocol/STLedgerEntry.h>
+#include <xrpl/protocol/STObject.h>
+#include <xrpl/protocol/STTx.h>
+#include <xrpl/protocol/SeqProxy.h>
+#include <xrpl/protocol/TER.h>
+#include <xrpl/protocol/TxFormats.h>
+#include <xrpl/protocol/XRPAmount.h>
+#include <xrpl/tx/ApplyContext.h>
+
+#include <algorithm>
+#include <array>
+#include <cstddef>
+#include <cstdint>
+#include <initializer_list>
+#include <memory>
+#include <optional>
+#include <source_location>
+#include <string>
+#include <utility>
+#include <vector>
+
+namespace xrpl::test {
+
+class InvariantsTransactionProposal_test : public InvariantsBase
+{
+    void
+    testTransactionProposalInvariants()
+    {
+        using namespace jtx;
+        using namespace std::chrono_literals;
+
+        // Submits a real proposal, so the entry is in the closed ledger before
+        // the precheck runs and the precheck can modify it.
+        std::optional<Keylet> liveProposalKeylet;
+        std::optional<std::uint32_t> liveTicketSeq;
+        Preclose const precloseLiveProposal =
+            [&](Account const& owner, Account const& destination, Env& env) {
+                auto const ticketSeq = proposal::createTicket(env, owner);
+                auto const proposedTx =
+                    proposal::unsignedPayload(env, pay(owner, destination, XRP(1)), ticketSeq);
+                liveProposalKeylet = keylet::txProposal(owner.id(), ticketSeq);
+                liveTicketSeq = ticketSeq;
+                env(proposal::create(owner, proposedTx, proposal::expiration(env, 100s)));
+                return BEAST_EXPECT(env.le(*liveProposalKeylet));
+            };
+
+        auto peekLiveProposal = [&](ApplyContext& ac) -> SLE::pointer {
+            if (!liveProposalKeylet)
+                return nullptr;
+            return ac.view().peek(*liveProposalKeylet);
+        };
+
+        // Deletes the live proposal as deleteProposal would: out of the
+        // owner's directory, with the owner's reserve released.
+        auto deleteLiveProposal = [&](Account const& owner, ApplyContext& ac) {
+            auto const sle = peekLiveProposal(ac);
+            if (!sle)
+                return false;
+            auto const account = ac.view().peek(keylet::account(owner.id()));
+            if (!account)
+                return false;
+            account->at(sfOwnerCount) -=
+                xrpl::proposal::proposalOwnerCount(sle->getFieldObject(sfProposedTransaction));
+            ac.view().update(account);
+            if (!ac.view().dirRemove(
+                    keylet::ownerDir(owner.id()), sle->getFieldU64(sfOwnerNode), sle->key(), false))
+                return false;
+            ac.view().erase(sle);
+            return true;
+        };
+
+        // Consumes one of the owner's Tickets as ticketDelete would.
+        auto deleteTicket = [&](Account const& owner, std::uint32_t ticketSeq, ApplyContext& ac) {
+            auto const ticket =
+                ac.view().peek(keylet::ticket(owner.id(), SeqProxy::rawTicket(ticketSeq)));
+            auto const account = ac.view().peek(keylet::account(owner.id()));
+            if (!ticket || !account)
+                return false;
+            if (!ac.view().dirRemove(
+                    keylet::ownerDir(owner.id()),
+                    ticket->getFieldU64(sfOwnerNode),
+                    ticket->key(),
+                    false))
+                return false;
+            if (auto const ticketCount = account->getFieldU32(sfTicketCount); ticketCount > 1)
+            {
+                account->setFieldU32(sfTicketCount, ticketCount - 1);
+            }
+            else
+            {
+                account->makeFieldAbsent(sfTicketCount);
+            }
+            account->at(sfOwnerCount) -= 1;
+            ac.view().update(account);
+            ac.view().erase(ticket);
+            return true;
+        };
+
+        // A transaction outside the whitelist may not modify a proposal at
+        // all; the invariant rejects it on the count, whatever field changed.
+        testcase("TransactionProposal modified outside the whitelist");
+        doInvariantCheck(
+            {{"TransactionProposal changes do not match transaction result"}},
+            [&](Account const&, Account const&, ApplyContext& ac) {
+                auto const sle = peekLiveProposal(ac);
+                if (!sle)
+                    return false;
+                auto proposedTx = sle->getFieldObject(sfProposedTransaction);
+                proposedTx.setFieldU32(
+                    sfTicketSequence, proposedTx.getFieldU32(sfTicketSequence) + 1);
+                sle->setFieldObject(sfProposedTransaction, proposedTx);
+                ac.view().update(sle);
+                return true;
+            },
+            XRPAmount{},
+            STTx{ttACCOUNT_SET, [](STObject&) {}},
+            {tecINVARIANT_FAILED, tefINVARIANT_FAILED},
+            precloseLiveProposal);
+
+        // Only stages the payload and the key it would live under; nothing
+        // reaches the ledger, so a precheck that inserts the entry by hand
+        // presents the invariant with a creation.
+        std::optional<STObject> stagedPayload;
+        std::optional<Keylet> stagedProposalKeylet;
+        Preclose const precloseStagedPayload =
+            [&](Account const& owner, Account const& destination, Env& env) {
+                auto const ticketSeq = proposal::createTicket(env, owner);
+                auto const proposedJson =
+                    proposal::unsignedPayload(env, pay(owner, destination, XRP(1)), ticketSeq);
+                stagedPayload.emplace(parse(proposedJson));
+                stagedProposalKeylet = keylet::txProposal(owner.id(), ticketSeq);
+                return true;
+            };
+
+        // Inserts the staged proposal as doApply would, with the owner's
+        // reserve charged.
+        auto insertStagedProposal = [&](Account const& owner, ApplyContext& ac) {
+            if (!stagedPayload || !stagedProposalKeylet)
+                return false;
+
+            auto const sle = std::make_shared<SLE>(*stagedProposalKeylet);
+            sle->setAccountID(sfOwner, owner.id());
+            sle->setFieldObject(sfProposedTransaction, *stagedPayload);
+            sle->setFieldU32(sfExpiration, 1);
+            sle->setFieldU64(sfOwnerNode, 0);
+            ac.view().insert(sle);
+
+            auto const account = ac.view().peek(keylet::account(owner.id()));
+            if (!account)
+                return false;
+            account->at(sfOwnerCount) += xrpl::proposal::proposalOwnerCount(*stagedPayload);
+            ac.view().update(account);
+            return true;
+        };
+
+        testcase("TransactionProposal effect whitelist");
+        doInvariantCheck(
+            {{"TransactionProposal changes do not match transaction result"}},
+            [&](Account const& owner, Account const&, ApplyContext& ac) {
+                return insertStagedProposal(owner, ac);
+            },
+            XRPAmount{},
+            STTx{ttACCOUNT_SET, [](STObject&) {}},
+            {tecINVARIANT_FAILED, tefINVARIANT_FAILED},
+            precloseStagedPayload);
+
+        // The harness runs no transactor, so a failed result has to be fed in
+        // directly. A failed create must leave no trace.
+        testcase("TransactionProposal failed create still inserts");
+        doInvariantCheck(
+            {{"TransactionProposal changes do not match transaction result"}},
+            [&](Account const& owner, Account const&, ApplyContext& ac) {
+                return insertStagedProposal(owner, ac);
+            },
+            XRPAmount{},
+            STTx{ttTRANSACTION_PROPOSAL_CREATE, [](STObject&) {}},
+            {tecINVARIANT_FAILED, tefINVARIANT_FAILED},
+            precloseStagedPayload,
+            TxAccount::None,
+            std::source_location::current(),
+            tecNO_PERMISSION);
+
+        // Reassigns the live proposal's reserve to a sponsor as a
+        // SponsorshipTransfer would. The sponsored and sponsoring counts move
+        // with it so that SponsorshipOwnerCountsMatch stays quiet.
+        auto const reassignLiveProposal =
+            [&](Account const& owner, Account const& sponsor, ApplyContext& ac) {
+                auto const sle = peekLiveProposal(ac);
+                if (!sle)
+                    return false;
+                auto const reserve =
+                    xrpl::proposal::proposalOwnerCount(sle->getFieldObject(sfProposedTransaction));
+                sle->setAccountID(sfSponsor, sponsor.id());
+                ac.view().update(sle);
+
+                auto const account = ac.view().peek(keylet::account(owner.id()));
+                auto const sponsorRoot = ac.view().peek(keylet::account(sponsor.id()));
+                if (!account || !sponsorRoot)
+                    return false;
+                account->at(sfSponsoredOwnerCount) += reserve;
+                ac.view().update(account);
+                sponsorRoot->at(sfSponsoringOwnerCount) += reserve;
+                ac.view().update(sponsorRoot);
+                return true;
+            };
+
+        // A failed transfer must not have reassigned anything. The counters are
+        // kept consistent so only the result mismatch is left to catch.
+        testcase("TransactionProposal failed sponsorship transfer still reassigns");
+        doInvariantCheck(
+            {{"TransactionProposal changes do not match transaction result"}},
+            reassignLiveProposal,
+            XRPAmount{},
+            STTx{ttSPONSORSHIP_TRANSFER, [](STObject&) {}},
+            {tecINVARIANT_FAILED, tefINVARIANT_FAILED},
+            precloseLiveProposal,
+            TxAccount::None,
+            std::source_location::current(),
+            tecNO_PERMISSION);
+
+        // A proposal leaves the ledger only through TransactionProposalCancel
+        // or together with the Ticket it is keyed to. The harness runs no
+        // transactor, so each deletion below is staged by hand, releasing the
+        // reserve as a real one would, to leave the deletion itself as the
+        // only possible violation.
+        testcase("TransactionProposal deletion outside the whitelist");
+        doInvariantCheck(
+            {{"TransactionProposal changes do not match transaction result"}},
+            [&](Account const& owner, Account const&, ApplyContext& ac) {
+                return deleteLiveProposal(owner, ac);
+            },
+            XRPAmount{},
+            STTx{ttACCOUNT_SET, [](STObject&) {}},
+            {tecINVARIANT_FAILED, tefINVARIANT_FAILED},
+            precloseLiveProposal);
+
+        // The owner holds a second Ticket, one no proposal is keyed to.
+        std::optional<std::uint32_t> spareTicketSeq;
+        Preclose const precloseLiveProposalAndSpareTicket =
+            [&](Account const& owner, Account const& destination, Env& env) {
+                spareTicketSeq = proposal::createTicket(env, owner);
+                return precloseLiveProposal(owner, destination, env);
+            };
+
+        // Consuming some other Ticket of the owner's is no reason for the
+        // proposal to go.
+        testcase("TransactionProposal deleted with an unrelated ticket");
+        doInvariantCheck(
+            {{"TransactionProposal changes do not match transaction result"}},
+            [&](Account const& owner, Account const&, ApplyContext& ac) {
+                return spareTicketSeq && deleteTicket(owner, *spareTicketSeq, ac) &&
+                    deleteLiveProposal(owner, ac);
+            },
+            XRPAmount{},
+            STTx{ttACCOUNT_SET, [](STObject&) {}},
+            {tecINVARIANT_FAILED, tefINVARIANT_FAILED},
+            precloseLiveProposalAndSpareTicket);
+
+        // And a deleted Ticket takes the proposal keyed to it along: here the
+        // Ticket went and the proposal stayed behind.
+        testcase("TransactionProposal outlives its ticket");
+        doInvariantCheck(
+            {{"TransactionProposal outlived the Ticket it is keyed to"}},
+            [&](Account const& owner, Account const&, ApplyContext& ac) {
+                return liveTicketSeq && deleteTicket(owner, *liveTicketSeq, ac);
+            },
+            XRPAmount{},
+            STTx{ttACCOUNT_SET, [](STObject&) {}},
+            {tecINVARIANT_FAILED, tefINVARIANT_FAILED},
+            precloseLiveProposal);
+
+        // A Cancel names the live proposal and may pay with the owner's spare
+        // Ticket. Both exist only once the preclose has run, so the Env is
+        // built here rather than by the harness.
+        struct CancelOptions
+        {
+            // The Cancel pays with A1's spare Ticket.
+            bool paySpareTicket = false;
+            TER initialResult = tesSUCCESS;
+        };
+        auto const checkCancel = [&](std::vector<std::string> const& expectLogs,
+                                     Precheck const& precheck,
+                                     std::initializer_list<TER> ters,
+                                     Preclose const& preclose,
+                                     CancelOptions const& options = CancelOptions(),
+                                     std::source_location const& loc =
+                                         std::source_location::current()) {
+            Account const a1{"A1"};
+            Account const a2{"A2"};
+            Env env = makeEnv(testableAmendments());
+            env.fund(XRP(1000), a1, a2);
+            if (!BEAST_EXPECT(preclose(a1, a2, env)) || !BEAST_EXPECT(liveProposalKeylet))
+                return;
+            env.close();
+
+            STTx const tx{ttTRANSACTION_PROPOSAL_CANCEL, [&](STObject& obj) {
+                              obj.setAccountID(sfAccount, a1.id());
+                              obj.setFieldH256(sfProposalID, liveProposalKeylet->key);
+                              if (options.paySpareTicket && spareTicketSeq)
+                              {
+                                  obj.setFieldU32(sfSequence, 0);
+                                  obj.setFieldU32(sfTicketSequence, *spareTicketSeq);
+                              }
+                          }};
+            doInvariantCheck(
+                std::move(env),
+                a1,
+                a2,
+                expectLogs,
+                precheck,
+                XRPAmount{},
+                tx,
+                ters,
+                loc,
+                options.initialResult);
+        };
+
+        auto const cancelDeletesLiveProposal =
+            [&](Account const& owner, Account const&, ApplyContext& ac) {
+                return deleteLiveProposal(owner, ac);
+            };
+
+        // A Cancel that did not succeed deleted nothing.
+        testcase("TransactionProposal failed cancel still deletes");
+        {
+            CancelOptions options;
+            options.initialResult = tecNO_PERMISSION;
+            checkCancel(
+                {{"TransactionProposal changes do not match transaction result"}},
+                cancelDeletesLiveProposal,
+                {tecINVARIANT_FAILED, tefINVARIANT_FAILED},
+                precloseLiveProposal,
+                options);
+        }
+
+        // A Cancel cannot spend a reserved Ticket, so the proposal it deletes
+        // never goes with its Ticket.
+        testcase("TransactionProposal cancel consumes the reserved ticket");
+        checkCancel(
+            {{"TransactionProposal changes do not match transaction result"}},
+            [&](Account const& owner, Account const&, ApplyContext& ac) {
+                return liveTicketSeq && deleteTicket(owner, *liveTicketSeq, ac) &&
+                    deleteLiveProposal(owner, ac);
+            },
+            {tecINVARIANT_FAILED, tefINVARIANT_FAILED},
+            precloseLiveProposal);
+
+        // Distinct AccountIDs in ascending order, so an array built from them
+        // violates only the bound on its length.
+        auto ascendingAccounts = [](std::size_t count) {
+            std::vector<AccountID> accounts;
+            accounts.reserve(count);
+            for (std::size_t i = 0; i < count; ++i)
+            {
+                AccountID account{beast::kZero};
+                account.data()[0] = static_cast<std::uint8_t>(i + 1);
+                accounts.push_back(account);
+            }
+            return accounts;
+        };
+
+        auto signerArray = [](std::vector<AccountID> const& accounts) {
+            STArray signers{sfSigners};
+            for (auto const& account : accounts)
+            {
+                STObject signer{sfSigner};
+                signer.setAccountID(sfAccount, account);
+                signers.pushBack(signer);
+            }
+            return signers;
+        };
+
+        // No transaction type on this amendment branch collects signatures yet,
+        // so every rejection below has to be provoked by editing the stored
+        // payload directly.
+        auto const testBrokenSignerArray = [&](std::string const& name, auto const& breakPayload) {
+            testcase("TransactionProposal canonical signer arrays: " + name);
+            doInvariantCheck(
+                {{"TransactionProposal signer arrays are not canonical"}},
+                [&](Account const&, Account const& signerAccount, ApplyContext& ac) {
+                    auto const sle = peekLiveProposal(ac);
+                    if (!sle)
+                        return false;
+                    auto proposedTx = sle->getFieldObject(sfProposedTransaction);
+                    breakPayload(proposedTx, signerAccount);
+                    sle->setFieldObject(sfProposedTransaction, proposedTx);
+                    ac.view().update(sle);
+                    return true;
+                },
+                XRPAmount{},
+                STTx{ttACCOUNT_SET, [](STObject&) {}},
+                {tecINVARIANT_FAILED, tefINVARIANT_FAILED},
+                precloseLiveProposal);
+        };
+
+        testBrokenSignerArray("duplicate entries", [&](STObject& tx, Account const& signer) {
+            tx.setFieldArray(sfSigners, signerArray({signer.id(), signer.id()}));
+        });
+
+        testBrokenSignerArray("descending order", [&](STObject& tx, Account const&) {
+            auto accounts = ascendingAccounts(2);
+            std::ranges::reverse(accounts);
+            tx.setFieldArray(sfSigners, signerArray(accounts));
+        });
+
+        testBrokenSignerArray("past the multi-sign limit", [&](STObject& tx, Account const&) {
+            tx.setFieldArray(sfSigners, signerArray(ascendingAccounts(STTx::kMaxMultiSigners + 1)));
+        });
+
+        testBrokenSignerArray("entry without an Account", [](STObject& tx, Account const&) {
+            STArray signers{sfSigners};
+            signers.pushBack(STObject{sfSigner});
+            tx.setFieldArray(sfSigners, signers);
+        });
+
+        for (auto const* field :
+             std::array<SField const*, 2>{&sfCounterpartySignature, &sfSponsorSignature})
+        {
+            testBrokenSignerArray(
+                "duplicates under " + field->getName(), [&](STObject& tx, Account const& signer) {
+                    STObject signature{*field};
+                    signature.setFieldArray(sfSigners, signerArray({signer.id(), signer.id()}));
+                    tx.setFieldObject(*field, signature);
+                });
+        }
+
+        testBrokenSignerArray("past the batch-signer limit", [&](STObject& tx, Account const&) {
+            STArray batchSigners{sfBatchSigners};
+            for (auto const& account : ascendingAccounts(kMaxBatchSigners + 1))
+            {
+                STObject batchSigner{sfBatchSigner};
+                batchSigner.setAccountID(sfAccount, account);
+                batchSigners.pushBack(batchSigner);
+            }
+            tx.setFieldArray(sfBatchSigners, batchSigners);
+        });
+
+        testBrokenSignerArray(
+            "duplicates under a BatchSigner", [&](STObject& tx, Account const& signer) {
+                STObject batchSigner{sfBatchSigner};
+                batchSigner.setAccountID(sfAccount, signer.id());
+                batchSigner.setFieldArray(sfSigners, signerArray({signer.id(), signer.id()}));
+
+                STArray batchSigners{sfBatchSigners};
+                batchSigners.pushBack(batchSigner);
+                tx.setFieldArray(sfBatchSigners, batchSigners);
+            });
+
+        // Negative controls. These share the setup of the failure cases above,
+        // so they confirm each of those failures came from the defect it names
+        // rather than from the hand-built ledger state.
+        std::initializer_list<TER> const passTers = {tesSUCCESS, tesSUCCESS};
+
+        testcase("TransactionProposal well-formed create");
+        doInvariantCheck(
+            {},
+            [&](Account const& owner, Account const&, ApplyContext& ac) {
+                return insertStagedProposal(owner, ac);
+            },
+            XRPAmount{},
+            STTx{ttTRANSACTION_PROPOSAL_CREATE, [](STObject&) {}},
+            passTers,
+            precloseStagedPayload);
+
+        testcase("TransactionProposal left untouched");
+        doInvariantCheck(
+            {},
+            [&](Account const&, Account const&, ApplyContext& ac) {
+                return liveProposalKeylet && ac.view().read(*liveProposalKeylet) != nullptr;
+            },
+            XRPAmount{},
+            STTx{ttACCOUNT_SET, [](STObject&) {}},
+            passTers,
+            precloseLiveProposal);
+
+        // A Cancel deletes the proposal it names.
+        testcase("TransactionProposal cancelled");
+        checkCancel({}, cancelDeletesLiveProposal, passTers, precloseLiveProposal);
+
+        // The Ticket a Cancel pays with is not the one its proposal is keyed
+        // to, so the proposal did not go with its Ticket.
+        testcase("TransactionProposal cancel paid with the canceller's own ticket");
+        {
+            CancelOptions options;
+            options.paySpareTicket = true;
+            checkCancel(
+                {},
+                [&](Account const& owner, Account const&, ApplyContext& ac) {
+                    return spareTicketSeq && deleteTicket(owner, *spareTicketSeq, ac) &&
+                        deleteLiveProposal(owner, ac);
+                },
+                passTers,
+                precloseLiveProposalAndSpareTicket,
+                options);
+        }
+
+        // A SponsorshipTransfer reassigns the Sponsor.
+        testcase("TransactionProposal sponsor reassigned");
+        doInvariantCheck(
+            {},
+            reassignLiveProposal,
+            XRPAmount{},
+            STTx{ttSPONSORSHIP_TRANSFER, [](STObject&) {}},
+            passTers,
+            precloseLiveProposal);
+
+        // The proposed transaction executing spends the proposal's Ticket and
+        // takes the proposal with it.
+        testcase("TransactionProposal deleted with its ticket");
+        doInvariantCheck(
+            {},
+            [&](Account const& owner, Account const&, ApplyContext& ac) {
+                return liveTicketSeq && deleteTicket(owner, *liveTicketSeq, ac) &&
+                    deleteLiveProposal(owner, ac);
+            },
+            XRPAmount{},
+            STTx{ttACCOUNT_SET, [](STObject&) {}},
+            passTers,
+            precloseLiveProposal);
+    }
+
+    void
+    run() override
+    {
+        testTransactionProposalInvariants();
+    }
+};
+
+BEAST_DEFINE_TESTSUITE(InvariantsTransactionProposal, app, xrpl);
+
+}  // namespace xrpl::test

src/test/app/lending/LoanBroker_test.cpp

@@ -1154,6 +1154,8 @@ class LoanBroker_test : public beast::unit_test::Suite
             auto const jrr = env.rpc("submit", strHex(s.slice()))[jss::result];
             // fails in doSubmit() on STTx construction
             BEAST_EXPECT(jrr[jss::error] == "invalidTransaction");
+            BEAST_EXPECT(!jrr.isMember(jss::error_code));
+            BEAST_EXPECT(jrr[jss::error_message].isNull());
             BEAST_EXPECT(jrr[jss::error_exception] == "invalid native account");
         }
 

src/test/app/lending/LoanLifecycle_test.cpp

@@ -190,6 +190,8 @@ private:
             BEAST_EXPECT(jr.isMember(jss::result));
             auto const jResult = jr[jss::result];
             BEAST_EXPECT(jResult[jss::error] == "invalidTransaction");
+            BEAST_EXPECT(!jResult.isMember(jss::error_code));
+            BEAST_EXPECT(jResult[jss::error_message].isNull());
             BEAST_EXPECT(
                 jResult[jss::error_exception] ==
                 "fails local checks: Transaction has bad signature.");

src/test/app/lending/LoanMisc_test.cpp

@@ -18,6 +18,7 @@
 #include <xrpl/beast/xor_shift_engine.h>
 #include <xrpl/json/json_value.h>
 #include <xrpl/json/to_string.h>
+#include <xrpl/protocol/ErrorCodes.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/Indexes.h>
 #include <xrpl/protocol/KeyType.h>
@@ -126,12 +127,9 @@ private:
                     return params;
                 }();
                 auto const jSignBorrower = env.rpc("json", "sign", to_string(borrowerSignParams));
-                BEAST_EXPECT(
-                    jSignBorrower.isMember(jss::result) &&
-                    jSignBorrower[jss::result].isMember(jss::error) &&
-                    jSignBorrower[jss::result][jss::error] == "invalidParams" &&
-                    jSignBorrower[jss::result].isMember(jss::error_message) &&
-                    jSignBorrower[jss::result][jss::error_message] == target);
+                BEAST_EXPECT(jSignBorrower[jss::result][jss::error] == "invalidParams");
+                BEAST_EXPECT(jSignBorrower[jss::result][jss::error_code] == RpcInvalidParams);
+                BEAST_EXPECT(jSignBorrower[jss::result][jss::error_message] == target);
             }
         }
         {

src/test/app/lending/LoanValidation_test.cpp

@@ -196,7 +196,8 @@ private:
             jvResult[jss::tx_blob] = strHex(local.getSerializer().slice());
             auto res = env.rpc("json", "submit", to_string(jvResult))["result"];
             BEAST_EXPECT(
-                res[jss::error] == "invalidTransaction" &&
+                res[jss::error] == "invalidTransaction" && !res.isMember(jss::error_code) &&
+                res[jss::error_message].isNull() &&
                 res[jss::error_exception] ==
                     "fails local checks: Counterparty: Invalid signature.");
         });

src/test/app/vault/VaultLifecycle_test.cpp

@@ -15,6 +15,7 @@
 #include <test/jtx/ter.h>
 #include <test/jtx/ticket.h>
 #include <test/jtx/trust.h>
+#include <test/jtx/txflags.h>
 #include <test/jtx/vault.h>
 
 #include <xrpl/basics/Number.h>
@@ -1609,26 +1610,263 @@ private:
             env.close();
 
             // Direct vault share payment inherits the underlying lock via
-            // sfReferenceHolding.
+            // sfReferenceHolding. Caught in the strand check, like a global
+            // or individual share lock.
             BEAST_EXPECT(shareBalance(alice) == 499);
             BEAST_EXPECT(shareBalance(bob) == 501);
-            env(pay(alice, bob, shares(1)), Ter{tecLOCKED});
+            env(pay(alice, bob, shares(1)), Ter{tecPATH_DRY});
             env.close();
             BEAST_EXPECT(shareBalance(alice) == 499);
             BEAST_EXPECT(shareBalance(bob) == 501);
 
             // The same inherited lock must also block DEX payment paths that
-            // would consume an offer selling vault shares.
+            // would consume an offer selling vault shares. bob, the
+            // destination, inherits the lock and is caught in the strand
+            // check.
             env(pay(carol, bob, shares(1)),
                 Sendmax(XRP(1)),
                 Path(BookSpec{shares.raw()}),
-                Ter{tecPATH_PARTIAL});
+                Ter{tecPATH_DRY});
             env.close();
             BEAST_EXPECT(shareBalance(alice) == 499);
             BEAST_EXPECT(shareBalance(bob) == 501);
             BEAST_EXPECT(expectOffers(env, alice, 1));
         }
 
+        // A holder individually frozen on the underlying can neither sell
+        // nor buy vault shares through an unfrozen holder's offer. The
+        // inherited freeze is caught when the strand is built, before the
+        // offer is consumed.
+        auto const testShareDEXEndpointFrozen =
+            [&](Env& env,
+                PrettyAsset const& asset,
+                Account const& owner,
+                Account const& alice,
+                Account const& bob,
+                Account const& carol,
+                std::function<void(bool)> const& setAliceFrozen) {
+                Vault const vault{env};
+                auto [tx, keylet] = vault.create({.owner = owner, .asset = asset});
+                env(tx);
+                env.close();
+
+                env(vault.deposit({.depositor = alice, .id = keylet.key, .amount = asset(500)}));
+                env(vault.deposit({.depositor = bob, .id = keylet.key, .amount = asset(500)}));
+                env.close();
+
+                PrettyAsset const shares = MPTIssue(env.le(keylet)->at(sfShareMPTID));
+                auto const shareMptID = shares.raw().get<MPTIssue>().getMptID();
+                auto const shareBalance = [&](Account const& account) {
+                    auto const sle = env.le(keylet::mptoken(shareMptID, account));
+                    return sle ? sle->at(sfMPTAmount) : 0;
+                };
+
+                // bob bids XRP for shares and asks more XRP for shares, so that
+                // his offers don't cross
+                env(offer(bob, shares(1), XRP(1)));
+                env(offer(bob, XRP(2), shares(1)));
+                env.close();
+
+                setAliceFrozen(true);
+
+                auto const aliceShares = shareBalance(alice);
+                auto const bobShares = shareBalance(bob);
+                auto const expectUnchanged = [&] {
+                    BEAST_EXPECT(shareBalance(alice) == aliceShares);
+                    BEAST_EXPECT(shareBalance(bob) == bobShares);
+                    BEAST_EXPECT(expectOffers(env, bob, 2));
+                };
+
+                // alice sells shares: the first step's source is frozen
+                env(pay(alice, carol, XRP(1)),
+                    Sendmax(shares(1)),
+                    Path(~XRP),
+                    Txflags(tfNoRippleDirect),
+                    Ter{tecPATH_DRY});
+                env.close();
+                expectUnchanged();
+
+                // carol buys shares for alice: the last step's destination is
+                // frozen
+                env(pay(carol, alice, shares(1)),
+                    Sendmax(XRP(2)),
+                    Path(BookSpec{shares.raw()}),
+                    Txflags(tfNoRippleDirect),
+                    Ter{tecPATH_DRY});
+                env.close();
+                expectUnchanged();
+
+                // Both succeed once alice is unfrozen
+                setAliceFrozen(false);
+
+                env(pay(alice, carol, XRP(1)),
+                    Sendmax(shares(1)),
+                    Path(~XRP),
+                    Txflags(tfNoRippleDirect));
+                env.close();
+                BEAST_EXPECT(shareBalance(bob) == bobShares + 1);
+
+                env(pay(carol, alice, shares(1)),
+                    Sendmax(XRP(2)),
+                    Path(BookSpec{shares.raw()}),
+                    Txflags(tfNoRippleDirect));
+                env.close();
+                BEAST_EXPECT(shareBalance(alice) == aliceShares);
+                BEAST_EXPECT(shareBalance(bob) == bobShares);
+                BEAST_EXPECT(expectOffers(env, bob, 0));
+            };
+
+        // Vault shares as the intermediate asset between two books. Only the
+        // offer owners hold the shares in transit. An owner individually
+        // frozen on the underlying can neither give nor receive the shares.
+        auto const testShareDEXMiddleFrozen = [&](Env& env,
+                                                  PrettyAsset const& asset,
+                                                  Account const& owner,
+                                                  Account const& alice,
+                                                  Account const& bob,
+                                                  Account const& carol,
+                                                  std::function<void(bool)> const& setAliceFrozen) {
+            Vault const vault{env};
+            auto [tx, keylet] = vault.create({.owner = owner, .asset = asset});
+            env(tx);
+            env.close();
+
+            env(vault.deposit({.depositor = alice, .id = keylet.key, .amount = asset(500)}));
+            env(vault.deposit({.depositor = bob, .id = keylet.key, .amount = asset(500)}));
+            env.close();
+
+            PrettyAsset const shares = MPTIssue(env.le(keylet)->at(sfShareMPTID));
+            auto const shareMptID = shares.raw().get<MPTIssue>().getMptID();
+            auto const shareBalance = [&](Account const& account) {
+                auto const sle = env.le(keylet::mptoken(shareMptID, account));
+                return sle ? sle->at(sfMPTAmount) : 0;
+            };
+
+            // alice gives the shares: XRP -> shares (alice) -> asset (bob)
+            {
+                env(offer(alice, XRP(1), shares(1)));
+                env(offer(bob, shares(1), asset(1)));
+                env.close();
+
+                setAliceFrozen(true);
+
+                auto const aliceShares = shareBalance(alice);
+                auto const bobShares = shareBalance(bob);
+                env(pay(carol, owner, asset(1)),
+                    Sendmax(XRP(1)),
+                    Path(BookSpec{shares.raw()}, BookSpec{asset.raw()}),
+                    Txflags(tfNoRippleDirect),
+                    Ter{tecPATH_PARTIAL});
+                env.close();
+                BEAST_EXPECT(shareBalance(alice) == aliceShares);
+                BEAST_EXPECT(shareBalance(bob) == bobShares);
+
+                setAliceFrozen(false);
+
+                env(pay(carol, owner, asset(1)),
+                    Sendmax(XRP(1)),
+                    Path(BookSpec{shares.raw()}, BookSpec{asset.raw()}),
+                    Txflags(tfNoRippleDirect));
+                env.close();
+                BEAST_EXPECT(shareBalance(alice) == aliceShares - 1);
+                BEAST_EXPECT(shareBalance(bob) == bobShares + 1);
+                BEAST_EXPECT(expectOffers(env, alice, 0));
+                BEAST_EXPECT(expectOffers(env, bob, 0));
+            }
+
+            // alice receives the shares: asset -> shares (bob) -> XRP (alice)
+            {
+                env(offer(bob, asset(1), shares(1)));
+                env(offer(alice, shares(1), XRP(1)));
+                env.close();
+
+                setAliceFrozen(true);
+
+                auto const aliceShares = shareBalance(alice);
+                auto const bobShares = shareBalance(bob);
+                env(pay(owner, carol, XRP(1)),
+                    Sendmax(asset(1)),
+                    Path(BookSpec{shares.raw()}, ~XRP),
+                    Txflags(tfNoRippleDirect),
+                    Ter{tecPATH_PARTIAL});
+                env.close();
+                BEAST_EXPECT(shareBalance(alice) == aliceShares);
+                BEAST_EXPECT(shareBalance(bob) == bobShares);
+
+                setAliceFrozen(false);
+
+                env(pay(owner, carol, XRP(1)),
+                    Sendmax(asset(1)),
+                    Path(BookSpec{shares.raw()}, ~XRP),
+                    Txflags(tfNoRippleDirect));
+                env.close();
+                BEAST_EXPECT(shareBalance(alice) == aliceShares + 1);
+                BEAST_EXPECT(shareBalance(bob) == bobShares - 1);
+                BEAST_EXPECT(expectOffers(env, alice, 0));
+                BEAST_EXPECT(expectOffers(env, bob, 0));
+            }
+        };
+
+        {
+            testcase("MPT individually locked: vault share DEX inherits underlying lock");
+
+            Env env{*this, testableAmendments()};
+            Account const issuer{"issuer"};
+            Account const owner{"owner"};
+            Account const alice{"alice"};
+            Account const bob{"bob"};
+            Account const carol{"carol"};
+            env.fund(XRP(10'000), issuer, owner, alice, bob, carol);
+            env.close();
+
+            MPTTester asset{{
+                .env = env,
+                .issuer = issuer,
+                .holders = {owner, alice, bob},
+                .flags = tfMPTCanTransfer | tfMPTCanTrade | tfMPTCanLock,
+            }};
+            env(pay(issuer, owner, asset(1'000)));
+            env(pay(issuer, alice, asset(2'000)));
+            env(pay(issuer, bob, asset(2'000)));
+            env.close();
+
+            auto const setAliceFrozen = [&](bool frozen) {
+                asset.set({.holder = alice, .flags = frozen ? tfMPTLock : tfMPTUnlock});
+                env.close();
+            };
+            testShareDEXEndpointFrozen(env, asset, owner, alice, bob, carol, setAliceFrozen);
+            testShareDEXMiddleFrozen(env, asset, owner, alice, bob, carol, setAliceFrozen);
+        }
+
+        {
+            testcase("IOU individually frozen: vault share DEX inherits underlying freeze");
+
+            Env env{*this, testableAmendments()};
+            Account const issuer{"issuer"};
+            Account const owner{"owner"};
+            Account const alice{"alice"};
+            Account const bob{"bob"};
+            Account const carol{"carol"};
+            env.fund(XRP(10'000), issuer, owner, alice, bob, carol);
+            env.close();
+
+            // Deliver the IOU from a book to a holder
+            env(fset(issuer, asfDefaultRipple));
+            PrettyAsset const asset = issuer["IOU"];
+            env.trust(asset(10'000), owner, alice, bob);
+            env(pay(issuer, owner, asset(1'000)));
+            env(pay(issuer, alice, asset(2'000)));
+            env(pay(issuer, bob, asset(2'000)));
+            env.close();
+
+            auto const setAliceFrozen = [&](bool frozen) {
+                env(trust(issuer, asset(0), alice, frozen ? tfSetFreeze : tfClearFreeze));
+                env.close();
+            };
+            testShareDEXEndpointFrozen(env, asset, owner, alice, bob, carol, setAliceFrozen);
+            testShareDEXMiddleFrozen(env, asset, owner, alice, bob, carol, setAliceFrozen);
+        }
+
         {
             testcase("MPT CanTrade governance: share inherits underlying on DEX and AMM");
 

src/test/app/vault/VaultRPC_test.cpp

@@ -172,7 +172,7 @@ private:
             jvParams[jss::ledger_index] = jss::validated;
             jvParams[jss::vault] = to_string(UInt256(42));
             auto jvVault = env.rpc("json", "ledger_entry", to_string(jvParams));
-            BEAST_EXPECT(jvVault[jss::result][jss::error].asString() == "entryNotFound");
+            checkError(jvVault[jss::result], "entryNotFound", RpcEntryNotFound, "Entry not found.");
         }
 
         {
@@ -182,7 +182,7 @@ private:
             jvParams[jss::vault][jss::owner] = issuer.human();
             jvParams[jss::vault][jss::seq] = 1'000'000;
             auto jvVault = env.rpc("json", "ledger_entry", to_string(jvParams));
-            BEAST_EXPECT(jvVault[jss::result][jss::error].asString() == "entryNotFound");
+            checkError(jvVault[jss::result], "entryNotFound", RpcEntryNotFound, "Entry not found.");
         }
 
         {
@@ -191,7 +191,11 @@ private:
             jvParams[jss::ledger_index] = jss::validated;
             jvParams[jss::vault] = 42;
             auto jvVault = env.rpc("json", "ledger_entry", to_string(jvParams));
-            BEAST_EXPECT(jvVault[jss::result][jss::error].asString() == "malformedRequest");
+            checkError(
+                jvVault[jss::result],
+                "malformedRequest",
+                RpcInvalidParams,
+                "Invalid field 'vault', not hex string or object.");
         }
 
         {
@@ -201,7 +205,11 @@ private:
             jvParams[jss::vault][jss::owner] = 42;
             jvParams[jss::vault][jss::seq] = sequence;
             auto jvVault = env.rpc("json", "ledger_entry", to_string(jvParams));
-            BEAST_EXPECT(jvVault[jss::result][jss::error].asString() == "malformedOwner");
+            checkError(
+                jvVault[jss::result],
+                "malformedOwner",
+                RpcInvalidParams,
+                "Invalid field 'owner', not AccountID.");
         }
 
         {
@@ -211,7 +219,11 @@ private:
             jvParams[jss::vault][jss::owner] = issuer.human();
             jvParams[jss::vault][jss::seq] = "foo";
             auto jvVault = env.rpc("json", "ledger_entry", to_string(jvParams));
-            BEAST_EXPECT(jvVault[jss::result][jss::error].asString() == "malformedRequest");
+            checkError(
+                jvVault[jss::result],
+                "malformedRequest",
+                RpcInvalidParams,
+                "Invalid field 'seq', not number.");
         }
 
         {
@@ -221,7 +233,11 @@ private:
             jvParams[jss::vault][jss::owner] = issuer.human();
             jvParams[jss::vault][jss::seq] = -1;
             auto jvVault = env.rpc("json", "ledger_entry", to_string(jvParams));
-            BEAST_EXPECT(jvVault[jss::result][jss::error].asString() == "malformedRequest");
+            checkError(
+                jvVault[jss::result],
+                "malformedRequest",
+                RpcInvalidParams,
+                "Invalid field 'seq', not number.");
         }
 
         {
@@ -231,7 +247,11 @@ private:
             jvParams[jss::vault][jss::owner] = issuer.human();
             jvParams[jss::vault][jss::seq] = 1e20;
             auto jvVault = env.rpc("json", "ledger_entry", to_string(jvParams));
-            BEAST_EXPECT(jvVault[jss::result][jss::error].asString() == "malformedRequest");
+            checkError(
+                jvVault[jss::result],
+                "malformedRequest",
+                RpcInvalidParams,
+                "Invalid field 'seq', not number.");
         }
 
         {
@@ -241,7 +261,11 @@ private:
             jvParams[jss::vault][jss::owner] = issuer.human();
             jvParams[jss::vault][jss::seq] = true;
             auto jvVault = env.rpc("json", "ledger_entry", to_string(jvParams));
-            BEAST_EXPECT(jvVault[jss::result][jss::error].asString() == "malformedRequest");
+            checkError(
+                jvVault[jss::result],
+                "malformedRequest",
+                RpcInvalidParams,
+                "Invalid field 'seq', not number.");
         }
 
         {
@@ -500,8 +524,8 @@ private:
 
         {
             testcase("RPC vault_info command line invalid index");
-            json::Value jv = env.rpc("vault_info", "foobar", "validated");
-            BEAST_EXPECT(jv[jss::error].asString() == "invalidParams");
+            json::Value const jv = env.rpc("vault_info", "foobar", "validated");
+            checkError(jv, "invalidParams", RpcInvalidParams, "Invalid parameters.");
         }
 
         {
@@ -519,7 +543,7 @@ private:
         {
             testcase("RPC vault_info command line invalid ledger");
             json::Value jv = env.rpc("vault_info", strHex(keylet.key), "0");
-            BEAST_EXPECT(jv[jss::result][jss::error].asString() == "lgrNotFound");
+            checkError(jv[jss::result], "lgrNotFound", RpcLgrNotFound, "ledgerNotFound");
         }
     }
 

src/test/jtx/escrow.h

@@ -2,8 +2,11 @@
 
 #include <test/jtx/Account.h>
 #include <test/jtx/Env.h>
+#include <test/jtx/JTx.h>
 #include <test/jtx/TestHelpers.h>
 
+#include <xrpl/basics/Slice.h>
+#include <xrpl/basics/strHex.h>
 #include <xrpl/json/json_value.h>
 #include <xrpl/protocol/AccountID.h>
 #include <xrpl/protocol/Rate.h>
@@ -11,7 +14,10 @@
 #include <xrpl/protocol/STAmount.h>
 
 #include <array>
+#include <cstddef>
 #include <cstdint>
+#include <string>
+#include <utility>
 
 /**
  * Escrow operations.
@@ -95,4 +101,55 @@ auto const kCondition = JTxFieldWrapper<BlobField>(sfCondition);
 
 auto const kFulfillment = JTxFieldWrapper<BlobField>(sfFulfillment);
 
+/**
+ * Set a hex-encoded blob field on a JTx
+ */
+template <SF_VL const& Field>
+struct HexBlobField
+{
+private:
+    std::string value_;
+
+public:
+    explicit HexBlobField(std::string hex) : value_(std::move(hex))
+    {
+    }
+
+    explicit HexBlobField(Slice const& blob) : value_(strHex(blob))
+    {
+    }
+
+    template <size_t N>
+    explicit HexBlobField(std::array<std::uint8_t, N> const& blob) : HexBlobField(makeSlice(blob))
+    {
+    }
+
+    void
+    operator()(Env&, JTx& jt) const
+    {
+        // clang-tidy reads a reference template parameter as parenthesized.
+        jt.jv[Field.jsonName] = value_;  // NOLINT(readability-redundant-parentheses)
+    }
+};
+
+using Bytecode = HexBlobField<sfBytecode>;
+using Data = HexBlobField<sfData>;
+
+struct Gas
+{
+private:
+    std::uint32_t value_;
+
+public:
+    explicit Gas(std::uint32_t const value) : value_(value)
+    {
+    }
+
+    void
+    operator()(Env&, JTx& jt) const
+    {
+        jt.jv[sfGas.jsonName] = value_;
+    }
+};
+
 }  // namespace xrpl::test::jtx::escrow

src/test/jtx/impl/proposal.cpp

@@ -238,6 +238,13 @@ verify::Create::operator()(Env& env, JTx& jt) const
     // Every entry the transaction could touch, read whole, so what follows can
     // say that nothing moved rather than that the fields we named did not.
     auto const& view = *env.current();
+
+    // A proposer paying with one of its own Tickets consumes it whenever the
+    // transaction is applied: on success, and on a claimed-fee tec.
+    std::optional<std::uint32_t> ownTicketSeq;
+    if (jt.jv.isMember(sfTicketSequence.jsonName))
+        ownTicketSeq = jt.jv[sfTicketSequence.jsonName].asUInt();
+
     auto const proposalKeylet = keylet::txProposal(target, ticketSeq);
     auto const ownerCountBefore = env.ownerCount(proposer);
     auto const sponsoredOwnerCountBefore = env.sponsoredOwnerCount(proposer);
@@ -254,11 +261,15 @@ verify::Create::operator()(Env& env, JTx& jt) const
         auto const& view = *applied.current();
 
         auto const created = isTesSuccess(applied.ter());
+        bool const ticketConsumed = ownTicketSeq && (created || isTecClaim(applied.ter()));
+        std::uint32_t const ticketReturned = ticketConsumed ? 1 : 0;
 
         // The proposer owns the proposal even when another account covers its
-        // reserve. A proposed Batch costs more owner-count increments.
+        // reserve. A proposed Batch costs more owner-count increments. A
+        // Ticket the proposer paid with gives one back.
         test.expect(
-            applied.ownerCount(proposer) == ownerCountBefore + (created ? cost : 0),
+            applied.ownerCount(proposer) ==
+                ownerCountBefore + (created ? cost : 0) - ticketReturned,
             "proposal reserve");
         test.expect(
             applied.sponsoredOwnerCount(proposer) ==
@@ -291,6 +302,14 @@ verify::Create::operator()(Env& env, JTx& jt) const
 
         auto const sleProposal = view.read(proposalKeylet);
 
+        // The Ticket the proposer paid with has left its directory.
+        auto expectedDir = proposerDirBefore;
+        if (ticketConsumed)
+        {
+            expectedDir.erase(
+                keylet::ticket(proposer.id(), SeqProxy::rawTicket(*ownTicketSeq)).key);
+        }
+
         if (!created)
         {
             // A create that did not succeed leaves the proposal as it found
@@ -300,7 +319,7 @@ verify::Create::operator()(Env& env, JTx& jt) const
             // Nor did the directory gain a listing for an entry that does not
             // exist.
             test.expect(
-                ownerDirKeys(view, proposer.id()) == proposerDirBefore, "proposal owner directory");
+                ownerDirKeys(view, proposer.id()) == expectedDir, "proposal owner directory");
             return;
         }
 
@@ -353,7 +372,6 @@ verify::Create::operator()(Env& env, JTx& jt) const
 
         // The proposal is listed in the proposer's directory on the page its
         // OwnerNode names, and nothing else listed moved.
-        auto expectedDir = proposerDirBefore;
         expectedDir.emplace(sleProposal->key(), sleProposal->getFieldU64(sfOwnerNode));
         test.expect(ownerDirKeys(view, proposer.id()) == expectedDir, "proposal owner directory");
     });

src/test/jtx/proposal.h

@@ -77,7 +77,9 @@ public:
  * @brief Check the ledger effects a TransactionProposalCreate must have,
  * whatever its outcome: on tesSUCCESS a new proposal holding what was
  * submitted, listed in the proposer's directory and paid for by its reserve;
- * otherwise nothing moved. Nothing of the target's moves either way.
+ * otherwise nothing moved. Nothing of the target's moves either way. A Ticket
+ * the proposer pays with is expected to be consumed; attach ticket::Use()
+ * before this condition so it sees the TicketSequence.
  *
  * @code
  * env(proposal::create(alice, payload, expiration), proposal::verify::create());

src/test/protocol/STIssue_test.cpp

@@ -12,6 +12,7 @@
 #include <xrpl/json/json_value.h>
 #include <xrpl/json/to_string.h>
 #include <xrpl/protocol/AccountID.h>
+#include <xrpl/protocol/ErrorCodes.h>
 #include <xrpl/protocol/Indexes.h>
 #include <xrpl/protocol/Issue.h>
 #include <xrpl/protocol/MPTIssue.h>
@@ -180,6 +181,7 @@ public:
         auto const result = env.rpc("json", "sign", to_string(req))[jss::result];
 
         BEAST_EXPECT(result[jss::error] == "invalidParams");
+        BEAST_EXPECT(result[jss::error_code] == RpcInvalidParams);
         BEAST_EXPECT(result[jss::error_message] == "Field 'tx_json.Asset' has invalid data.");
     }
 
@@ -253,6 +255,7 @@ public:
         auto const result = env.rpc("json", "sign", to_string(req))[jss::result];
 
         BEAST_EXPECT(result[jss::error] == "invalidParams");
+        BEAST_EXPECT(result[jss::error_code] == RpcInvalidParams);
         BEAST_EXPECT(result[jss::error_message] == "Field 'tx_json.Asset' has invalid data.");
     }
 

src/test/rpc/AMMInfo_test.cpp

@@ -8,6 +8,7 @@
 
 #include <xrpl/beast/unit_test/suite.h>
 #include <xrpl/protocol/AccountID.h>
+#include <xrpl/protocol/ErrorCodes.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/Issue.h>
 #include <xrpl/protocol/TxFlags.h>
@@ -56,12 +57,16 @@ public:
             Account const gw("gw");
             auto const usd = gw["USD"];
             auto const jv = ammAlice.ammRpcInfo({}, {}, usd, usd);
+            BEAST_EXPECT(jv[jss::error] == "actNotFound");
+            BEAST_EXPECT(jv[jss::error_code] == RpcActNotFound);
             BEAST_EXPECT(jv[jss::error_message] == "Account not found.");
         });
 
         // Invalid LP account id
         testAMM([&](AMM& ammAlice, Env&) {
             auto const jv = ammAlice.ammRpcInfo(bogie.id());
+            BEAST_EXPECT(jv[jss::error] == "actMalformed");
+            BEAST_EXPECT(jv[jss::error_code] == RpcActMalformed);
             BEAST_EXPECT(jv[jss::error_message] == "Account malformed.");
         });
 
@@ -69,6 +74,8 @@ public:
         testAMM([&](AMM& ammAlice, Env&) {
             auto const jv =
                 ammAlice.ammRpcInfo(json::Value{42}, std::nullopt, XRP, USD, std::nullopt, true, 3);
+            BEAST_EXPECT(jv[jss::error] == "actMalformed");
+            BEAST_EXPECT(jv[jss::error_code] == RpcActMalformed);
             BEAST_EXPECT(jv[jss::error_message] == "Account malformed.");
         });
 
@@ -82,6 +89,8 @@ public:
                 json::Value{42},
                 false,
                 3);
+            BEAST_EXPECT(jv[jss::error] == "actMalformed");
+            BEAST_EXPECT(jv[jss::error_code] == RpcActMalformed);
             BEAST_EXPECT(jv[jss::error_message] == "Account malformed.");
         });
 
@@ -106,6 +115,8 @@ public:
                     iss2,
                     accountId(ammAlice, acct),
                     ignoreParams);
+                BEAST_EXPECT(jv[jss::error] == "invalidParams");
+                BEAST_EXPECT(jv[jss::error_code] == RpcInvalidParams);
                 BEAST_EXPECT(jv[jss::error_message] == "Invalid parameters.");
             }
         });
@@ -121,6 +132,8 @@ public:
                     iss2,
                     accountId(ammAlice, acct),
                     ignoreParams);
+                BEAST_EXPECT(jv[jss::error] == "invalidParams");
+                BEAST_EXPECT(jv[jss::error_code] == RpcInvalidParams);
                 BEAST_EXPECT(jv[jss::error_message] == "Invalid parameters.");
             }
         });
@@ -137,6 +150,8 @@ public:
                     accountId(ammAlice, acct),
                     ignoreParams,
                     3);
+                BEAST_EXPECT(jv[jss::error] == "actMalformed");
+                BEAST_EXPECT(jv[jss::error_code] == RpcActMalformed);
                 BEAST_EXPECT(jv[jss::error_message] == "Account malformed.");
             }
         });
@@ -145,6 +160,8 @@ public:
         testAMM([&](AMM& ammAlice, Env&) {
             auto const jv = ammAlice.ammRpcInfo(
                 std::nullopt, std::nullopt, std::nullopt, std::nullopt, bogie.id());
+            BEAST_EXPECT(jv[jss::error] == "actMalformed");
+            BEAST_EXPECT(jv[jss::error_code] == RpcActMalformed);
             BEAST_EXPECT(jv[jss::error_message] == "Account malformed.");
         });
 
@@ -169,6 +186,8 @@ public:
                     iss2,
                     accountId(ammAlice, acct),
                     ignoreParams);
+                BEAST_EXPECT(jv[jss::error] == "invalidParams");
+                BEAST_EXPECT(jv[jss::error_code] == RpcInvalidParams);
                 BEAST_EXPECT(jv[jss::error_message] == "Invalid parameters.");
             }
         });
@@ -185,6 +204,13 @@ public:
                     accountId(ammAlice, acct),
                     ignoreParams,
                     3);
+                BEAST_EXPECT(
+                    jv[jss::error] ==
+                    (acct == TestAccount::Bogie ? std::string("actMalformed")
+                                                : std::string("invalidParams")));
+                BEAST_EXPECT(
+                    jv[jss::error_code] ==
+                    (acct == TestAccount::Bogie ? RpcActMalformed : RpcInvalidParams));
                 BEAST_EXPECT(
                     jv[jss::error_message] ==
                     (acct == TestAccount::Bogie ? std::string("Account malformed.")
@@ -383,7 +409,9 @@ public:
         testAMM([&](AMM& amm, Env&) {
             auto const resp = amm.ammRpcInfo(
                 std::nullopt, jss::validated.cStr(), std::nullopt, std::nullopt, gw_);
-            BEAST_EXPECT(resp.isMember("error") && resp["error"] == "actNotFound");
+            BEAST_EXPECT(resp[jss::error] == "actNotFound");
+            BEAST_EXPECT(resp[jss::error_code] == RpcActNotFound);
+            BEAST_EXPECT(resp[jss::error_message] == "Account not found.");
         });
     }
 

src/test/rpc/AccountInfo_test.cpp

@@ -16,6 +16,7 @@
 
 #include <array>
 #include <cstdint>
+#include <format>
 #include <optional>
 #include <string_view>
 #include <utility>
@@ -34,6 +35,8 @@ public:
         {
             // account_info with no account.
             auto const info = env.rpc("json", "account_info", "{ }");
+            BEAST_EXPECT(info[jss::result][jss::error] == "invalidParams");
+            BEAST_EXPECT(info[jss::result][jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(info[jss::result][jss::error_message] == "Missing field 'account'.");
         }
         {
@@ -43,8 +46,11 @@ public:
                 "account_info",
                 "{\"account\": "
                 "\"n94JNrQYkDrpt62bbSR7nVEhdyAvcJXRAsjEkFYyqRkh9SUTYEqV\"}");
+            BEAST_EXPECT(info[jss::result][jss::error] == "actMalformed");
             BEAST_EXPECT(info[jss::result][jss::error_code] == RpcActMalformed);
             BEAST_EXPECT(info[jss::result][jss::error_message] == "Account malformed.");
+            BEAST_EXPECT(info[jss::result].isMember(jss::ledger_current_index));
+            BEAST_EXPECT(info[jss::result][jss::validated] == false);
         }
         {
             // account_info with an account that's not in the ledger.
@@ -52,12 +58,17 @@ public:
             json::Value params;
             params[jss::account] = bogie.human();
             auto const info = env.rpc("json", "account_info", to_string(params));
+            BEAST_EXPECT(info[jss::result][jss::error] == "actNotFound");
             BEAST_EXPECT(info[jss::result][jss::error_code] == RpcActNotFound);
             BEAST_EXPECT(info[jss::result][jss::error_message] == "Account not found.");
+            BEAST_EXPECT(info[jss::result][jss::account] == bogie.human());
+            BEAST_EXPECT(info[jss::result].isMember(jss::ledger_current_index));
+            BEAST_EXPECT(info[jss::result][jss::validated] == false);
         }
         {
             // Cannot use a seed as account
-            auto const info = env.rpc("json", "account_info", R"({"account": "foo"})");
+            auto const info = env.rpc("json", "account_info", R"JSON({"account": "foo"})JSON");
+            BEAST_EXPECT(info[jss::result][jss::error] == "actMalformed");
             BEAST_EXPECT(info[jss::result][jss::error_code] == RpcActMalformed);
             BEAST_EXPECT(info[jss::result][jss::error_message] == "Account malformed.");
         }
@@ -69,6 +80,7 @@ public:
                 params[jss::account] = param;
                 auto jrr = env.rpc("json", "account_info", to_string(params))[jss::result];
                 BEAST_EXPECT(jrr[jss::error] == "invalidParams");
+                BEAST_EXPECT(jrr[jss::error_code] == RpcInvalidParams);
                 BEAST_EXPECT(jrr[jss::error_message] == "Invalid field 'account'.");
             };
 
@@ -87,6 +99,7 @@ public:
                 params[jss::ident] = param;
                 auto jrr = env.rpc("json", "account_info", to_string(params))[jss::result];
                 BEAST_EXPECT(jrr[jss::error] == "invalidParams");
+                BEAST_EXPECT(jrr[jss::error_code] == RpcInvalidParams);
                 BEAST_EXPECT(jrr[jss::error_message] == "Invalid field 'ident'.");
             };
 
@@ -97,6 +110,41 @@ public:
             testInvalidIdentParam(json::Value(json::ValueType::Object));
             testInvalidIdentParam(json::Value(json::ValueType::Array));
         }
+        {
+            // `ident` is ignored when `account` is present
+            json::Value params;
+            params[jss::account] = env.master.human();
+            params[jss::ident] = 1;
+            auto const info = env.rpc("json", "account_info", to_string(params))[jss::result];
+            BEAST_EXPECT(!info.isMember(jss::error));
+            BEAST_EXPECT(info.isMember(jss::account_data));
+            BEAST_EXPECT(info[jss::account_data][sfAccount.jsonName] == env.master.human());
+        }
+        {
+            // an invalid ledger is reported before a missing account
+            json::Value params;
+            params[jss::ledger_hash] = 1;
+            auto const info = env.rpc("json", "account_info", to_string(params))[jss::result];
+            BEAST_EXPECT(info[jss::error] == "invalidParams");
+            BEAST_EXPECT(info[jss::error_code] == RpcInvalidParams);
+            BEAST_EXPECT(
+                info[jss::error_message] == "Invalid field 'ledger_hash', not hex string.");
+        }
+        {
+            // `queue` is read as a bool, so any non-empty string requests it, and the queue
+            // can't be requested from a closed ledger
+            env.close();
+            json::Value params;
+            params[jss::account] = env.master.human();
+            params[jss::ledger_index] = "closed";
+            params[jss::queue] = "false";
+            auto const info = env.rpc("json", "account_info", to_string(params))[jss::result];
+            BEAST_EXPECT(info[jss::error] == "invalidParams");
+            BEAST_EXPECT(info[jss::error_code] == RpcInvalidParams);
+            BEAST_EXPECT(info[jss::error_message] == "Invalid parameters.");
+            BEAST_EXPECT(info.isMember(jss::ledger_index));
+            BEAST_EXPECT(!info.isMember(jss::account_data));
+        }
     }
 
     // Test the "signer_lists" argument in account_info.
@@ -234,8 +282,9 @@ public:
         withSigners[jss::account] = alice.human();
         withSigners[jss::signer_lists] = true;
 
-        auto const withSignersAsString = std::string("{ ") + R"("api_version": 2, "account": ")" +
-            alice.human() + "\", " + "\"signer_lists\": asdfggh }";
+        auto const withSignersAsString = std::format(
+            R"JSON({{"api_version": 2, "account": "{}", "signer_lists": "yes"}})JSON",
+            alice.human());
 
         // Alice has no SignerList yet.
         {
@@ -285,9 +334,15 @@ public:
         }
         {
             // account_info with "signer_lists" as not bool should error out
-            auto const info = env.rpc("json", "account_info", withSignersAsString);
+            auto const info = env.rpc("json", "account_info", withSignersAsString)[jss::result];
             BEAST_EXPECT(info[jss::status] == "error");
             BEAST_EXPECT(info[jss::error] == "invalidParams");
+            BEAST_EXPECT(info[jss::error_code] == RpcInvalidParams);
+            BEAST_EXPECT(info[jss::error_message] == "Invalid parameters.");
+            BEAST_EXPECT(info.isMember(jss::account_data));
+            BEAST_EXPECT(info[jss::account_data][sfAccount.jsonName] == alice.human());
+            BEAST_EXPECT(info.isMember(jss::ledger_current_index));
+            BEAST_EXPECT(!info.isMember(jss::signer_lists));
         }
 
         // Give alice a big signer list

src/test/rpc/AccountLines_test.cpp

@@ -48,9 +48,15 @@ public:
 
         using namespace test::jtx;
         Env env(*this);
+
+        static constexpr std::size_t kLinesPerGateway = 26;
+        static constexpr std::size_t kAllLines = 2 * kLinesPerGateway;
+
         {
             // account_lines with no account.
             auto const lines = env.rpc("json", "account_lines", "{ }");
+            BEAST_EXPECT(lines[jss::result][jss::error] == "invalidParams");
+            BEAST_EXPECT(lines[jss::result][jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(
                 lines[jss::result][jss::error_message] ==
                 rpc::missingFieldError(jss::account)[jss::error_message]);
@@ -60,9 +66,35 @@ public:
             json::Value params;
             params[jss::account] = "n9MJkEKHDhy5eTLuHUQeAAjo382frHNbFK4C8hcwN4nwM2SrLdBj";
             auto const lines = env.rpc("json", "account_lines", to_string(params));
+            BEAST_EXPECT(lines[jss::result][jss::error] == "actMalformed");
+            BEAST_EXPECT(lines[jss::result][jss::error_code] == RpcActMalformed);
             BEAST_EXPECT(
                 lines[jss::result][jss::error_message] ==
                 rpc::makeError(RpcActMalformed)[jss::error_message]);
+            BEAST_EXPECT(lines[jss::result].isMember(jss::ledger_current_index));
+            BEAST_EXPECT(lines[jss::result][jss::validated] == false);
+        }
+        {
+            // An invalid ledger is reported before a missing account.
+            json::Value params;
+            params[jss::ledger_hash] = 1;
+            auto const lines = env.rpc("json", "account_lines", to_string(params))[jss::result];
+            BEAST_EXPECT(lines[jss::error] == "invalidParams");
+            BEAST_EXPECT(lines[jss::error_code] == RpcInvalidParams);
+            BEAST_EXPECT(
+                lines[jss::error_message] == "Invalid field 'ledger_hash', not hex string.");
+        }
+        {
+            // A bad limit is reported before an account that is not found.
+            json::Value params;
+            params[jss::account] = Account{"bogie"}.human();
+            params[jss::limit] = -1;
+            auto const lines = env.rpc("json", "account_lines", to_string(params))[jss::result];
+            BEAST_EXPECT(lines[jss::error] == "invalidParams");
+            BEAST_EXPECT(lines[jss::error_code] == RpcInvalidParams);
+            BEAST_EXPECT(
+                lines[jss::error_message] ==
+                rpc::expectedFieldMessage(jss::limit, "unsigned integer"));
         }
         {
             // test account non-string
@@ -71,6 +103,7 @@ public:
                 params[jss::account] = param;
                 auto jrr = env.rpc("json", "account_lines", to_string(params))[jss::result];
                 BEAST_EXPECT(jrr[jss::error] == "invalidParams");
+                BEAST_EXPECT(jrr[jss::error_code] == RpcInvalidParams);
                 BEAST_EXPECT(jrr[jss::error_message] == "Invalid field 'account'.");
             };
 
@@ -87,6 +120,8 @@ public:
             json::Value params;
             params[jss::account] = alice.human();
             auto const lines = env.rpc("json", "account_lines", to_string(params));
+            BEAST_EXPECT(lines[jss::result][jss::error] == "actNotFound");
+            BEAST_EXPECT(lines[jss::result][jss::error_code] == RpcActNotFound);
             BEAST_EXPECT(
                 lines[jss::result][jss::error_message] ==
                 rpc::makeError(RpcActNotFound)[jss::error_message]);
@@ -104,6 +139,7 @@ public:
                 params[jss::peer] = param;
                 auto jrr = env.rpc("json", "account_lines", to_string(params))[jss::result];
                 BEAST_EXPECT(jrr[jss::error] == "invalidParams");
+                BEAST_EXPECT(jrr[jss::error_code] == RpcInvalidParams);
                 BEAST_EXPECT(jrr[jss::error_message] == "Invalid field 'peer'.");
             };
 
@@ -128,6 +164,8 @@ public:
             params[jss::account] = alice.human();
             params[jss::ledger_index] = "nonsense";
             auto const lines = env.rpc("json", "account_lines", to_string(params));
+            BEAST_EXPECT(lines[jss::result][jss::error] == "invalidParams");
+            BEAST_EXPECT(lines[jss::result][jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(
                 lines[jss::result][jss::error_message] ==
                 "Invalid field 'ledger_index', not string or number.");
@@ -138,6 +176,8 @@ public:
             params[jss::account] = alice.human();
             params[jss::ledger_index] = 50000;
             auto const lines = env.rpc("json", "account_lines", to_string(params));
+            BEAST_EXPECT(lines[jss::result][jss::error] == "lgrNotFound");
+            BEAST_EXPECT(lines[jss::result][jss::error_code] == RpcLgrNotFound);
             BEAST_EXPECT(lines[jss::result][jss::error_message] == "ledgerNotFound");
         }
         // Create trust lines to share with alice.
@@ -191,7 +231,7 @@ public:
 
         // A re-usable test for historic ledgers.
         auto const testAccountLinesHistory =
-            [this, &env](Account const& account, LedgerHeader const& info, int count) {
+            [this, &env](Account const& account, LedgerHeader const& info, std::size_t count) {
                 // Get account_lines by ledger index.
                 json::Value paramsSeq;
                 paramsSeq[jss::account] = account.human();
@@ -213,10 +253,10 @@ public:
         testAccountLinesHistory(alice, ledger3Info, 0);
 
         // Alice should have 26 trust lines in ledger 4.
-        testAccountLinesHistory(alice, ledger4Info, 26);
+        testAccountLinesHistory(alice, ledger4Info, kLinesPerGateway);
 
         // Alice should have 52 trust lines in ledger 58.
-        testAccountLinesHistory(alice, ledger58Info, 52);
+        testAccountLinesHistory(alice, ledger58Info, kAllLines);
 
         {
             // Invalid to specify both index and hash
@@ -226,6 +266,7 @@ public:
             params[jss::ledger_index] = ledger58Info.seq;
             auto const lines = env.rpc("json", "account_lines", to_string(params))[jss::result];
             BEAST_EXPECT(lines[jss::error] == "invalidParams");
+            BEAST_EXPECT(lines[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(
                 lines[jss::error_message] ==
                 "Exactly one of 'ledger_hash' or 'ledger_index' can be "
@@ -238,6 +279,7 @@ public:
             params[jss::ledger_index] = json::ValueType::Object;
             auto const lines = env.rpc("json", "account_lines", to_string(params))[jss::result];
             BEAST_EXPECT(lines[jss::error] == "invalidParams");
+            BEAST_EXPECT(lines[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(
                 lines[jss::error_message] == "Invalid field 'ledger_index', not string or number.");
         }
@@ -247,7 +289,7 @@ public:
             params[jss::account] = alice.human();
             auto const lines = env.rpc("json", "account_lines", to_string(params));
             BEAST_EXPECT(lines[jss::result][jss::lines].isArray());
-            BEAST_EXPECT(lines[jss::result][jss::lines].size() == 52);
+            BEAST_EXPECT(lines[jss::result][jss::lines].size() == kAllLines);
         }
         {
             // alice should have 26 trust lines with gw1.
@@ -256,7 +298,7 @@ public:
             params[jss::peer] = gw1.human();
             auto const lines = env.rpc("json", "account_lines", to_string(params));
             BEAST_EXPECT(lines[jss::result][jss::lines].isArray());
-            BEAST_EXPECT(lines[jss::result][jss::lines].size() == 26);
+            BEAST_EXPECT(lines[jss::result][jss::lines].size() == kLinesPerGateway);
 
             // Check no ripple is not set for trustlines between alice and gw1
             auto const& line = lines[jss::result][jss::lines][0u];
@@ -268,9 +310,39 @@ public:
             params[jss::account] = alice.human();
             params[jss::peer] = "n9MJkEKHDhy5eTLuHUQeAAjo382frHNbFK4C8hcwN4nwM2SrLdBj";
             auto const lines = env.rpc("json", "account_lines", to_string(params));
+            BEAST_EXPECT(lines[jss::result][jss::error] == "actMalformed");
+            BEAST_EXPECT(lines[jss::result][jss::error_code] == RpcActMalformed);
             BEAST_EXPECT(
                 lines[jss::result][jss::error_message] ==
                 rpc::makeError(RpcActMalformed)[jss::error_message]);
+            BEAST_EXPECT(lines[jss::result].isMember(jss::ledger_current_index));
+            BEAST_EXPECT(lines[jss::result][jss::validated] == false);
+        }
+        {
+            // An empty peer is no peer at all.
+            json::Value params;
+            params[jss::account] = alice.human();
+            params[jss::peer] = "";
+            auto const lines = env.rpc("json", "account_lines", to_string(params));
+            params.removeMember(jss::peer);
+            auto const all = env.rpc("json", "account_lines", to_string(params));
+            BEAST_EXPECT(lines[jss::result][jss::lines].isArray());
+            BEAST_EXPECT(lines[jss::result][jss::lines].size() == kAllLines);
+            BEAST_EXPECT(lines[jss::result][jss::lines] == all[jss::result][jss::lines]);
+        }
+        {
+            // ignore_default is read as a bool, so any non-empty string sets it.
+            json::Value params;
+            params[jss::account] = gw1.human();
+            auto const all = env.rpc("json", "account_lines", to_string(params));
+            params[jss::ignore_default] = true;
+            auto const asBool = env.rpc("json", "account_lines", to_string(params));
+            params[jss::ignore_default] = "false";
+            auto const asString = env.rpc("json", "account_lines", to_string(params));
+            BEAST_EXPECT(all[jss::result][jss::lines].size() == kLinesPerGateway);
+            BEAST_EXPECT(asBool[jss::result][jss::lines].size() == 0);
+            BEAST_EXPECT(!asString[jss::result].isMember(jss::error));
+            BEAST_EXPECT(asString[jss::result][jss::lines] == asBool[jss::result][jss::lines]);
         }
         {
             // A negative limit should fail.
@@ -278,6 +350,8 @@ public:
             params[jss::account] = alice.human();
             params[jss::limit] = -1;
             auto const lines = env.rpc("json", "account_lines", to_string(params));
+            BEAST_EXPECT(lines[jss::result][jss::error] == "invalidParams");
+            BEAST_EXPECT(lines[jss::result][jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(
                 lines[jss::result][jss::error_message] ==
                 rpc::expectedFieldMessage(jss::limit, "unsigned integer"));
@@ -298,7 +372,7 @@ public:
             paramsB[jss::marker] = marker;
             auto const linesB = env.rpc("json", "account_lines", to_string(paramsB));
             BEAST_EXPECT(linesB[jss::result][jss::lines].isArray());
-            BEAST_EXPECT(linesB[jss::result][jss::lines].size() == 51);
+            BEAST_EXPECT(linesB[jss::result][jss::lines].size() == kAllLines - 1);
 
             // Go again from where the marker left off, but set a limit of 3.
             json::Value paramsC;
@@ -315,6 +389,8 @@ public:
             paramsD[jss::account] = alice.human();
             paramsD[jss::marker] = marker;
             auto const linesD = env.rpc("json", "account_lines", to_string(paramsD));
+            BEAST_EXPECT(linesD[jss::result][jss::error] == "invalidParams");
+            BEAST_EXPECT(linesD[jss::result][jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(
                 linesD[jss::result][jss::error_message] ==
                 rpc::makeError(RpcInvalidParams)[jss::error_message]);
@@ -325,10 +401,46 @@ public:
             params[jss::account] = alice.human();
             params[jss::marker] = true;
             auto const lines = env.rpc("json", "account_lines", to_string(params));
+            BEAST_EXPECT(lines[jss::result][jss::error] == "invalidParams");
+            BEAST_EXPECT(lines[jss::result][jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(
                 lines[jss::result][jss::error_message] ==
                 rpc::expectedFieldMessage(jss::marker, "string"));
         }
+        {
+            // A marker that does not parse is reported without naming the field.
+            json::Value params;
+            params[jss::account] = alice.human();
+            params[jss::marker] = "NOT_A_MARKER";
+            auto const lines = env.rpc("json", "account_lines", to_string(params));
+            BEAST_EXPECT(lines[jss::result][jss::error] == "invalidParams");
+            BEAST_EXPECT(lines[jss::result][jss::error_code] == RpcInvalidParams);
+            BEAST_EXPECT(
+                lines[jss::result][jss::error_message] ==
+                rpc::makeError(RpcInvalidParams)[jss::error_message]);
+        }
+        {
+            // The marker's start hint may have a leading '+', and anything after a second
+            // comma is ignored.
+            json::Value params;
+            params[jss::account] = alice.human();
+            params[jss::limit] = 1;
+            auto const first = env.rpc("json", "account_lines", to_string(params));
+            auto const marker = first[jss::result][jss::marker].asString();
+            auto const comma = marker.find(',');
+            BEAST_EXPECT(comma != std::string::npos);
+
+            json::Value next;
+            next[jss::account] = alice.human();
+            next[jss::marker] = marker;
+            auto const plain = env.rpc("json", "account_lines", to_string(next));
+            next[jss::marker] =
+                marker.substr(0, comma) + ",+" + marker.substr(comma + 1) + ",ignored";
+            auto const lines = env.rpc("json", "account_lines", to_string(next));
+            BEAST_EXPECT(lines[jss::result][jss::lines].isArray());
+            BEAST_EXPECT(lines[jss::result][jss::lines].size() == kAllLines - 1);
+            BEAST_EXPECT(lines[jss::result][jss::lines] == plain[jss::result][jss::lines]);
+        }
         {
             // Check that the flags we expect from alice to gw2 are present.
             json::Value params;
@@ -446,7 +558,11 @@ public:
         beckyLinesParams[jss::account] = becky.human();
         beckyLinesParams[jss::marker] = aliceMarker;
         auto const beckyLines = env.rpc("json", "account_lines", to_string(beckyLinesParams));
-        BEAST_EXPECT(beckyLines[jss::result].isMember(jss::error_message));
+        BEAST_EXPECT(beckyLines[jss::result][jss::error] == "invalidParams");
+        BEAST_EXPECT(beckyLines[jss::result][jss::error_code] == RpcInvalidParams);
+        BEAST_EXPECT(
+            beckyLines[jss::result][jss::error_message] ==
+            rpc::makeError(RpcInvalidParams)[jss::error_message]);
     }
 
     void
@@ -514,6 +630,8 @@ public:
         linesEndParams[jss::account] = alice.human();
         linesEndParams[jss::marker] = linesBeg[jss::result][jss::marker];
         auto const linesEnd = env.rpc("json", "account_lines", to_string(linesEndParams));
+        BEAST_EXPECT(linesEnd[jss::result][jss::error] == "invalidParams");
+        BEAST_EXPECT(linesEnd[jss::result][jss::error_code] == RpcInvalidParams);
         BEAST_EXPECT(
             linesEnd[jss::result][jss::error_message] ==
             rpc::makeError(RpcInvalidParams)[jss::error_message]);
@@ -811,6 +929,8 @@ public:
             request[jss::ripplerpc] = "2.0";
             request[jss::id] = 5;
             auto const lines = env.rpc("json2", to_string(request));
+            BEAST_EXPECT(lines[jss::error][jss::error] == "invalidParams");
+            BEAST_EXPECT(lines[jss::error][jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(
                 lines[jss::error][jss::message] ==
                 rpc::missingFieldError(jss::account)[jss::error_message]);
@@ -829,6 +949,8 @@ public:
             request[jss::id] = 5;
             request[jss::params] = params;
             auto const lines = env.rpc("json2", to_string(request));
+            BEAST_EXPECT(lines[jss::error][jss::error] == "actMalformed");
+            BEAST_EXPECT(lines[jss::error][jss::error_code] == RpcActMalformed);
             BEAST_EXPECT(
                 lines[jss::error][jss::message] ==
                 rpc::makeError(RpcActMalformed)[jss::error_message]);
@@ -848,6 +970,8 @@ public:
             request[jss::id] = 5;
             request[jss::params] = params;
             auto const lines = env.rpc("json2", to_string(request));
+            BEAST_EXPECT(lines[jss::error][jss::error] == "actNotFound");
+            BEAST_EXPECT(lines[jss::error][jss::error_code] == RpcActNotFound);
             BEAST_EXPECT(
                 lines[jss::error][jss::message] ==
                 rpc::makeError(RpcActNotFound)[jss::error_message]);
@@ -876,6 +1000,7 @@ public:
 
                 auto const lines = env.rpc("json2", to_string(request));
                 BEAST_EXPECT(lines[jss::error][jss::error] == "invalidParams");
+                BEAST_EXPECT(lines[jss::error][jss::error_code] == RpcInvalidParams);
                 BEAST_EXPECT(lines[jss::error][jss::message] == "Invalid field 'peer'.");
                 BEAST_EXPECT(lines.isMember(jss::jsonrpc) && lines[jss::jsonrpc] == "2.0");
                 BEAST_EXPECT(lines.isMember(jss::ripplerpc) && lines[jss::ripplerpc] == "2.0");
@@ -918,6 +1043,8 @@ public:
             request[jss::id] = 5;
             request[jss::params] = params;
             auto const lines = env.rpc("json2", to_string(request));
+            BEAST_EXPECT(lines[jss::error][jss::error] == "invalidParams");
+            BEAST_EXPECT(lines[jss::error][jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(
                 lines[jss::error][jss::message] ==
                 "Invalid field 'ledger_index', not string or number.");
@@ -937,6 +1064,8 @@ public:
             request[jss::id] = 5;
             request[jss::params] = params;
             auto const lines = env.rpc("json2", to_string(request));
+            BEAST_EXPECT(lines[jss::error][jss::error] == "lgrNotFound");
+            BEAST_EXPECT(lines[jss::error][jss::error_code] == RpcLgrNotFound);
             BEAST_EXPECT(lines[jss::error][jss::message] == "ledgerNotFound");
             BEAST_EXPECT(lines.isMember(jss::jsonrpc) && lines[jss::jsonrpc] == "2.0");
             BEAST_EXPECT(lines.isMember(jss::ripplerpc) && lines[jss::ripplerpc] == "2.0");
@@ -1055,6 +1184,7 @@ public:
             request[jss::params] = params;
             auto const lines = env.rpc("json2", to_string(request));
             BEAST_EXPECT(lines[jss::error][jss::error] == "invalidParams");
+            BEAST_EXPECT(lines[jss::error][jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(
                 lines[jss::error][jss::message] ==
                 "Exactly one of 'ledger_hash' or 'ledger_index' can be "
@@ -1110,6 +1240,8 @@ public:
             request[jss::id] = 5;
             request[jss::params] = params;
             auto const lines = env.rpc("json2", to_string(request));
+            BEAST_EXPECT(lines[jss::error][jss::error] == "actMalformed");
+            BEAST_EXPECT(lines[jss::error][jss::error_code] == RpcActMalformed);
             BEAST_EXPECT(
                 lines[jss::error][jss::message] ==
                 rpc::makeError(RpcActMalformed)[jss::error_message]);
@@ -1129,6 +1261,8 @@ public:
             request[jss::id] = 5;
             request[jss::params] = params;
             auto const lines = env.rpc("json2", to_string(request));
+            BEAST_EXPECT(lines[jss::error][jss::error] == "invalidParams");
+            BEAST_EXPECT(lines[jss::error][jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(
                 lines[jss::error][jss::message] ==
                 rpc::expectedFieldMessage(jss::limit, "unsigned integer"));
@@ -1202,6 +1336,8 @@ public:
             requestD[jss::id] = 5;
             requestD[jss::params] = paramsD;
             auto const linesD = env.rpc("json2", to_string(requestD));
+            BEAST_EXPECT(linesD[jss::error][jss::error] == "invalidParams");
+            BEAST_EXPECT(linesD[jss::error][jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(
                 linesD[jss::error][jss::message] ==
                 rpc::makeError(RpcInvalidParams)[jss::error_message]);
@@ -1221,6 +1357,8 @@ public:
             request[jss::id] = 5;
             request[jss::params] = params;
             auto const lines = env.rpc("json2", to_string(request));
+            BEAST_EXPECT(lines[jss::error][jss::error] == "invalidParams");
+            BEAST_EXPECT(lines[jss::error][jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(
                 lines[jss::error][jss::message] ==
                 rpc::expectedFieldMessage(jss::marker, "string"));
@@ -1378,6 +1516,8 @@ public:
         linesEndRequest[jss::id] = 5;
         linesEndRequest[jss::params] = linesEndParams;
         auto const linesEnd = env.rpc("json2", to_string(linesEndRequest));
+        BEAST_EXPECT(linesEnd[jss::error][jss::error] == "invalidParams");
+        BEAST_EXPECT(linesEnd[jss::error][jss::error_code] == RpcInvalidParams);
         BEAST_EXPECT(
             linesEnd[jss::error][jss::message] ==
             rpc::makeError(RpcInvalidParams)[jss::error_message]);

src/test/rpc/AccountObjects_test.cpp

@@ -140,6 +140,8 @@ public:
         {
             json::Value const params;
             auto resp = env.rpc("json", "account_objects", to_string(params));
+            BEAST_EXPECT(resp[jss::result][jss::error] == "invalidParams");
+            BEAST_EXPECT(resp[jss::result][jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(resp[jss::result][jss::error_message] == "Missing field 'account'.");
         }
         // test account non-string
@@ -149,6 +151,7 @@ public:
                 params[jss::account] = param;
                 auto jrr = env.rpc("json", "account_objects", to_string(params))[jss::result];
                 BEAST_EXPECT(jrr[jss::error] == "invalidParams");
+                BEAST_EXPECT(jrr[jss::error_code] == RpcInvalidParams);
                 BEAST_EXPECT(jrr[jss::error_message] == "Invalid field 'account'.");
             };
 
@@ -164,6 +167,8 @@ public:
             json::Value params;
             params[jss::account] = "n94JNrQYkDrpt62bbSR7nVEhdyAvcJXRAsjEkFYyqRkh9SUTYEqV";
             auto resp = env.rpc("json", "account_objects", to_string(params));
+            BEAST_EXPECT(resp[jss::result][jss::error] == "actMalformed");
+            BEAST_EXPECT(resp[jss::result][jss::error_code] == RpcActMalformed);
             BEAST_EXPECT(resp[jss::result][jss::error_message] == "Account malformed.");
         }
         // test error on account that's not in the ledger.
@@ -171,6 +176,8 @@ public:
             json::Value params;
             params[jss::account] = Account{"bogie"}.human();
             auto resp = env.rpc("json", "account_objects", to_string(params));
+            BEAST_EXPECT(resp[jss::result][jss::error] == "actNotFound");
+            BEAST_EXPECT(resp[jss::result][jss::error_code] == RpcActNotFound);
             BEAST_EXPECT(resp[jss::result][jss::error_message] == "Account not found.");
         }
         Account const bob{"bob"};
@@ -180,6 +187,8 @@ public:
             params[jss::account] = bob.human();
             params[jss::ledger_index] = 10;
             auto resp = env.rpc("json", "account_objects", to_string(params));
+            BEAST_EXPECT(resp[jss::result][jss::error] == "lgrNotFound");
+            BEAST_EXPECT(resp[jss::result][jss::error_code] == RpcLgrNotFound);
             BEAST_EXPECT(resp[jss::result][jss::error_message] == "ledgerNotFound");
         }
 
@@ -190,6 +199,8 @@ public:
             params[jss::account] = bob.human();
             params[jss::type] = 10;
             auto resp = env.rpc("json", "account_objects", to_string(params));
+            BEAST_EXPECT(resp[jss::result][jss::error] == "invalidParams");
+            BEAST_EXPECT(resp[jss::result][jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(
                 resp[jss::result][jss::error_message] == "Invalid field 'type', not string.");
         }
@@ -199,6 +210,8 @@ public:
             params[jss::account] = bob.human();
             params[jss::type] = "expedited";
             auto resp = env.rpc("json", "account_objects", to_string(params));
+            BEAST_EXPECT(resp[jss::result][jss::error] == "invalidParams");
+            BEAST_EXPECT(resp[jss::result][jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(resp[jss::result][jss::error_message] == "Invalid field 'type'.");
         }
         // test error on limit -ve
@@ -207,6 +220,8 @@ public:
             params[jss::account] = bob.human();
             params[jss::limit] = -1;
             auto resp = env.rpc("json", "account_objects", to_string(params));
+            BEAST_EXPECT(resp[jss::result][jss::error] == "invalidParams");
+            BEAST_EXPECT(resp[jss::result][jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(
                 resp[jss::result][jss::error_message] ==
                 "Invalid field 'limit', not unsigned integer.");
@@ -217,6 +232,8 @@ public:
             params[jss::account] = bob.human();
             params[jss::sponsored] = "true";
             auto resp = env.rpc("json", "account_objects", to_string(params));
+            BEAST_EXPECT(resp[jss::result][jss::error] == "invalidParams");
+            BEAST_EXPECT(resp[jss::result][jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(
                 resp[jss::result][jss::error_message] == "Invalid field 'sponsored', not boolean.");
         }
@@ -238,27 +255,39 @@ public:
             std::string mark = to_string(resumeMarker);
             params[jss::marker] = 10;
             resp = env.rpc("json", "account_objects", to_string(params));
+            BEAST_EXPECT(resp[jss::result][jss::error] == "invalidParams");
+            BEAST_EXPECT(resp[jss::result][jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(
                 resp[jss::result][jss::error_message] == "Invalid field 'marker', not string.");
 
             params[jss::marker] = "This is a string with no comma";
             resp = env.rpc("json", "account_objects", to_string(params));
+            BEAST_EXPECT(resp[jss::result][jss::error] == "invalidParams");
+            BEAST_EXPECT(resp[jss::result][jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(resp[jss::result][jss::error_message] == "Invalid field 'marker'.");
 
             params[jss::marker] = "This string has a comma, but is not hex";
             resp = env.rpc("json", "account_objects", to_string(params));
+            BEAST_EXPECT(resp[jss::result][jss::error] == "invalidParams");
+            BEAST_EXPECT(resp[jss::result][jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(resp[jss::result][jss::error_message] == "Invalid field 'marker'.");
 
             params[jss::marker] = std::string(&mark[1U], 64);
             resp = env.rpc("json", "account_objects", to_string(params));
+            BEAST_EXPECT(resp[jss::result][jss::error] == "invalidParams");
+            BEAST_EXPECT(resp[jss::result][jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(resp[jss::result][jss::error_message] == "Invalid field 'marker'.");
 
             params[jss::marker] = std::string(&mark[1U], 65);
             resp = env.rpc("json", "account_objects", to_string(params));
+            BEAST_EXPECT(resp[jss::result][jss::error] == "invalidParams");
+            BEAST_EXPECT(resp[jss::result][jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(resp[jss::result][jss::error_message] == "Invalid field 'marker'.");
 
             params[jss::marker] = std::string(&mark[1U], 65) + "not hex";
             resp = env.rpc("json", "account_objects", to_string(params));
+            BEAST_EXPECT(resp[jss::result][jss::error] == "invalidParams");
+            BEAST_EXPECT(resp[jss::result][jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(resp[jss::result][jss::error_message] == "Invalid field 'marker'.");
 
             // Should this be an error?
@@ -603,7 +632,8 @@ public:
 
         // Make a lambda that checks if the response has error for invalid type
         auto const acctObjsTypeIsInvalid = [](json::Value const& resp) {
-            return resp[jss::result].isMember(jss::error) &&
+            return resp[jss::result][jss::error] == "invalidParams" &&
+                resp[jss::result][jss::error_code] == RpcInvalidParams &&
                 resp[jss::result][jss::error_message] == "Invalid field \'type\'.";
         };
 
@@ -1174,7 +1204,9 @@ public:
             params[jss::ledger_index] = jss::validated;
             params[jss::marker] = marker;
             json::Value const resp = env.rpc("json", "account_nfts", to_string(params));
-            return resp[jss::result][jss::error_message] == errorMessage;
+            return resp[jss::result][jss::error] == "invalidParams" &&
+                resp[jss::result][jss::error_code] == RpcInvalidParams &&
+                resp[jss::result][jss::error_message] == errorMessage;
         };
 
         // test an invalid marker that is not a string
@@ -1427,7 +1459,9 @@ public:
             params[jss::ledger_index] = jss::validated;
             params[jss::marker] = marker;
             json::Value const resp = env.rpc("json", "account_objects", to_string(params));
-            return resp[jss::result][jss::error_message] == "Invalid field \'marker\'.";
+            return resp[jss::result][jss::error] == "invalidParams" &&
+                resp[jss::result][jss::error_code] == RpcInvalidParams &&
+                resp[jss::result][jss::error_message] == "Invalid field \'marker\'.";
         };
 
         auto const markerStr = marker.asString();

src/test/rpc/AccountOffers_test.cpp

@@ -173,7 +173,9 @@ public:
             jvParams[jss::limit] = 0u;
             auto const jrr =
                 env.rpc("json", "account_offers", jvParams.toStyledString())[jss::result];
-            BEAST_EXPECT(jrr.isMember(jss::error_message));
+            BEAST_EXPECT(jrr[jss::error] == "invalidParams");
+            BEAST_EXPECT(jrr[jss::error_code] == RpcInvalidParams);
+            BEAST_EXPECT(jrr[jss::error_message] == "Invalid field 'limit'.");
         }
     }
 
@@ -195,9 +197,9 @@ public:
         {
             // no account field
             auto const jrr = env.rpc("account_offers");
+            BEAST_EXPECT(jrr[jss::status] == "error");
             BEAST_EXPECT(jrr[jss::error] == "badSyntax");
             BEAST_EXPECT(jrr[jss::error_code] == RpcBadSyntax);
-            BEAST_EXPECT(jrr[jss::status] == "error");
             BEAST_EXPECT(jrr[jss::error_message] == "Syntax error.");
         }
 
@@ -226,9 +228,9 @@ public:
             jvParams[jss::account] = "";
             auto const jrr =
                 env.rpc("json", "account_offers", jvParams.toStyledString())[jss::result];
+            BEAST_EXPECT(jrr[jss::status] == "error");
             BEAST_EXPECT(jrr[jss::error] == "actMalformed");
             BEAST_EXPECT(jrr[jss::error_code] == RpcActMalformed);
-            BEAST_EXPECT(jrr[jss::status] == "error");
             BEAST_EXPECT(jrr[jss::error_message] == "Account malformed.");
             BEAST_EXPECT(jrr.isMember(jss::ledger_current_index));
             BEAST_EXPECT(jrr[jss::validated] == false);
@@ -237,9 +239,9 @@ public:
         {
             // bogus account value
             auto const jrr = env.rpc("account_offers", Account("bogus").human())[jss::result];
+            BEAST_EXPECT(jrr[jss::status] == "error");
             BEAST_EXPECT(jrr[jss::error] == "actNotFound");
             BEAST_EXPECT(jrr[jss::error_code] == RpcActNotFound);
-            BEAST_EXPECT(jrr[jss::status] == "error");
             BEAST_EXPECT(jrr[jss::error_message] == "Account not found.");
         }
 
@@ -250,9 +252,9 @@ public:
             jvParams[jss::limit] = "0";  // NOT an integer
             auto const jrr =
                 env.rpc("json", "account_offers", jvParams.toStyledString())[jss::result];
+            BEAST_EXPECT(jrr[jss::status] == "error");
             BEAST_EXPECT(jrr[jss::error] == "invalidParams");
             BEAST_EXPECT(jrr[jss::error_code] == RpcInvalidParams);
-            BEAST_EXPECT(jrr[jss::status] == "error");
             BEAST_EXPECT(jrr[jss::error_message] == "Invalid field 'limit', not unsigned integer.");
         }
 
@@ -263,9 +265,9 @@ public:
             jvParams[jss::marker] = "NOT_A_MARKER";
             auto const jrr =
                 env.rpc("json", "account_offers", jvParams.toStyledString())[jss::result];
+            BEAST_EXPECT(jrr[jss::status] == "error");
             BEAST_EXPECT(jrr[jss::error] == "invalidParams");
             BEAST_EXPECT(jrr[jss::error_code] == RpcInvalidParams);
-            BEAST_EXPECT(jrr[jss::status] == "error");
             BEAST_EXPECTS(
                 jrr[jss::error_message] == "Invalid field 'marker'.", jrr.toStyledString());
         }
@@ -277,9 +279,9 @@ public:
             jvParams[jss::marker] = 1;
             auto const jrr =
                 env.rpc("json", "account_offers", jvParams.toStyledString())[jss::result];
+            BEAST_EXPECT(jrr[jss::status] == "error");
             BEAST_EXPECT(jrr[jss::error] == "invalidParams");
             BEAST_EXPECT(jrr[jss::error_code] == RpcInvalidParams);
-            BEAST_EXPECT(jrr[jss::status] == "error");
             BEAST_EXPECT(jrr[jss::error_message] == "Invalid field 'marker', not string.");
         }
 
@@ -290,9 +292,9 @@ public:
             jvParams[jss::ledger_index] = 10u;
             auto const jrr =
                 env.rpc("json", "account_offers", jvParams.toStyledString())[jss::result];
+            BEAST_EXPECT(jrr[jss::status] == "error");
             BEAST_EXPECT(jrr[jss::error] == "lgrNotFound");
             BEAST_EXPECT(jrr[jss::error_code] == RpcLgrNotFound);
-            BEAST_EXPECT(jrr[jss::status] == "error");
             BEAST_EXPECT(jrr[jss::error_message] == "ledgerNotFound");
         }
 

src/test/rpc/AccountTx_test.cpp

@@ -195,19 +195,27 @@ class AccountTx_test : public beast::unit_test::Suite
                 (j[jss::result][jss::transactions].size() == 0);
         };
 
-        auto const isErr = [](json::Value const& j, ErrorCodeI code) {
-            return j.isMember(jss::result) && j[jss::result].isMember(jss::error) &&
-                j[jss::result][jss::error] == rpc::getErrorInfo(code).token;
+        auto const isErr = [](json::Value const& j, ErrorCodeI code, std::string const& message) {
+            return j.isMember(jss::result) &&
+                j[jss::result][jss::error] == rpc::getErrorInfo(code).token &&
+                j[jss::result][jss::error_code] == code &&
+                j[jss::result][jss::error_message] == message;
         };
 
         json::Value jParams;
         jParams[jss::api_version] = apiVersion;
 
-        BEAST_EXPECT(isErr(env.rpc("json", "account_tx", to_string(jParams)), RpcInvalidParams));
+        BEAST_EXPECT(isErr(
+            env.rpc("json", "account_tx", to_string(jParams)),
+            RpcInvalidParams,
+            "Missing field 'account'."));
 
         jParams[jss::account] = "0xDEADBEEF";
 
-        BEAST_EXPECT(isErr(env.rpc("json", "account_tx", to_string(jParams)), RpcActMalformed));
+        BEAST_EXPECT(isErr(
+            env.rpc("json", "account_tx", to_string(jParams)),
+            RpcActMalformed,
+            "Account malformed."));
 
         jParams[jss::account] = a1.human();
         BEAST_EXPECT(hasTxs(env.rpc(apiVersion, "json", "account_tx", to_string(jParams))));
@@ -227,8 +235,10 @@ class AccountTx_test : public beast::unit_test::Suite
             }
             else
             {
-                BEAST_EXPECT(
-                    isErr(env.rpc("json", "account_tx", to_string(p)), RpcLgrIdxMalformed));
+                BEAST_EXPECT(isErr(
+                    env.rpc("json", "account_tx", to_string(p)),
+                    RpcLgrIdxMalformed,
+                    "Ledger index malformed."));
             }
 
             p[jss::ledger_index_min] = 1;
@@ -239,15 +249,18 @@ class AccountTx_test : public beast::unit_test::Suite
             }
             else
             {
-                BEAST_EXPECT(
-                    isErr(env.rpc("json", "account_tx", to_string(p)), RpcLgrIdxMalformed));
+                BEAST_EXPECT(isErr(
+                    env.rpc("json", "account_tx", to_string(p)),
+                    RpcLgrIdxMalformed,
+                    "Ledger index malformed."));
             }
 
             p[jss::ledger_index_min] = 2;
             p[jss::ledger_index_max] = 1;
             BEAST_EXPECT(isErr(
                 env.rpc("json", "account_tx", to_string(p)),
-                (apiVersion == 1 ? RpcLgrIdxsInvalid : RpcInvalidLgrRange)));
+                (apiVersion == 1 ? RpcLgrIdxsInvalid : RpcInvalidLgrRange),
+                (apiVersion == 1 ? "Ledger indexes invalid." : "Ledger range is invalid.")));
         }
         // Ledger index min only
         {
@@ -262,14 +275,17 @@ class AccountTx_test : public beast::unit_test::Suite
             }
             else
             {
-                BEAST_EXPECT(
-                    isErr(env.rpc("json", "account_tx", to_string(p)), RpcLgrIdxMalformed));
+                BEAST_EXPECT(isErr(
+                    env.rpc("json", "account_tx", to_string(p)),
+                    RpcLgrIdxMalformed,
+                    "Ledger index malformed."));
             }
 
             p[jss::ledger_index_min] = env.current()->header().seq;
             BEAST_EXPECT(isErr(
                 env.rpc("json", "account_tx", to_string(p)),
-                (apiVersion == 1 ? RpcLgrIdxsInvalid : RpcInvalidLgrRange)));
+                (apiVersion == 1 ? RpcLgrIdxsInvalid : RpcInvalidLgrRange),
+                (apiVersion == 1 ? "Ledger indexes invalid." : "Ledger range is invalid.")));
         }
 
         // Ledger index max only
@@ -285,8 +301,10 @@ class AccountTx_test : public beast::unit_test::Suite
             }
             else
             {
-                BEAST_EXPECT(
-                    isErr(env.rpc("json", "account_tx", to_string(p)), RpcLgrIdxMalformed));
+                BEAST_EXPECT(isErr(
+                    env.rpc("json", "account_tx", to_string(p)),
+                    RpcLgrIdxMalformed,
+                    "Ledger index malformed."));
             }
 
             p[jss::ledger_index_max] = 3;
@@ -310,10 +328,14 @@ class AccountTx_test : public beast::unit_test::Suite
             BEAST_EXPECT(noTxs(env.rpc("json", "account_tx", to_string(p))));
 
             p[jss::ledger_index] = env.current()->header().seq;
-            BEAST_EXPECT(isErr(env.rpc("json", "account_tx", to_string(p)), RpcLgrNotValidated));
+            BEAST_EXPECT(isErr(
+                env.rpc("json", "account_tx", to_string(p)),
+                RpcLgrNotValidated,
+                "Ledger not validated."));
 
             p[jss::ledger_index] = env.current()->header().seq + 1;
-            BEAST_EXPECT(isErr(env.rpc("json", "account_tx", to_string(p)), RpcLgrNotFound));
+            BEAST_EXPECT(isErr(
+                env.rpc("json", "account_tx", to_string(p)), RpcLgrNotFound, "ledgerNotFound"));
         }
 
         {
@@ -326,10 +348,16 @@ class AccountTx_test : public beast::unit_test::Suite
             BEAST_EXPECT(hasTxs(env.rpc(apiVersion, "json", "account_tx", to_string(p))));
 
             p[jss::ledger_index] = "current";
-            BEAST_EXPECT(isErr(env.rpc("json", "account_tx", to_string(p)), RpcLgrNotValidated));
+            BEAST_EXPECT(isErr(
+                env.rpc("json", "account_tx", to_string(p)),
+                RpcLgrNotValidated,
+                "Ledger not validated."));
 
             p[jss::ledger_index] = "";
-            BEAST_EXPECT(isErr(env.rpc("json", "account_tx", to_string(p)), RpcLgrNotValidated));
+            BEAST_EXPECT(isErr(
+                env.rpc("json", "account_tx", to_string(p)),
+                RpcLgrNotValidated,
+                "Ledger not validated."));
         }
 
         // Ledger Hash
@@ -360,7 +388,10 @@ class AccountTx_test : public beast::unit_test::Suite
             }
             else
             {
-                BEAST_EXPECT(isErr(env.rpc("json", "account_tx", to_string(p)), RpcInvalidParams));
+                BEAST_EXPECT(isErr(
+                    env.rpc("json", "account_tx", to_string(p)),
+                    RpcInvalidParams,
+                    "invalidParams"));
             }
         }
 
@@ -374,8 +405,10 @@ class AccountTx_test : public beast::unit_test::Suite
             }
             else
             {
-                BEAST_EXPECT(
-                    isErr(env.rpc("json", "account_tx", to_string(p)), RpcLgrIdxMalformed));
+                BEAST_EXPECT(isErr(
+                    env.rpc("json", "account_tx", to_string(p)),
+                    RpcLgrIdxMalformed,
+                    "Ledger index malformed."));
             }
         }
         // test account non-string
@@ -385,6 +418,7 @@ class AccountTx_test : public beast::unit_test::Suite
                 params[jss::account] = param;
                 auto jrr = env.rpc("json", "account_tx", to_string(params))[jss::result];
                 BEAST_EXPECT(jrr[jss::error] == "invalidParams");
+                BEAST_EXPECT(jrr[jss::error_code] == RpcInvalidParams);
                 BEAST_EXPECT(jrr[jss::error_message] == "Invalid field 'account'.");
             };
 
@@ -406,7 +440,10 @@ class AccountTx_test : public beast::unit_test::Suite
             }
             else
             {
-                BEAST_EXPECT(isErr(env.rpc("json", "account_tx", to_string(p)), RpcInvalidParams));
+                BEAST_EXPECT(isErr(
+                    env.rpc("json", "account_tx", to_string(p)),
+                    RpcInvalidParams,
+                    "Invalid field 'binary'."));
             }
 
             p[jss::binary] = true;
@@ -420,7 +457,10 @@ class AccountTx_test : public beast::unit_test::Suite
             }
             else
             {
-                BEAST_EXPECT(isErr(env.rpc("json", "account_tx", to_string(p)), RpcInvalidParams));
+                BEAST_EXPECT(isErr(
+                    env.rpc("json", "account_tx", to_string(p)),
+                    RpcInvalidParams,
+                    "Invalid field 'forward'."));
             }
 
             p[jss::forward] = false;
@@ -433,70 +473,83 @@ class AccountTx_test : public beast::unit_test::Suite
 
             // Test case: limit = 0 should fail (below minimum)
             p[jss::limit] = 0;
-            BEAST_EXPECT(isErr(env.rpc("json", "account_tx", to_string(p)), RpcInvalidParams));
+            BEAST_EXPECT(isErr(
+                env.rpc("json", "account_tx", to_string(p)),
+                RpcInvalidParams,
+                "Invalid field 'limit'."));
 
             // Test case: limit = 1.2 should fail (not an integer)
             p[jss::limit] = 1.2;
-            BEAST_EXPECT(
-                env.rpc("json", "account_tx", to_string(p))[jss::result][jss::error_message] ==
-                rpc::expectedFieldMessage(jss::limit, "unsigned integer"));
+            BEAST_EXPECT(isErr(
+                env.rpc("json", "account_tx", to_string(p)),
+                RpcInvalidParams,
+                rpc::expectedFieldMessage(jss::limit, "unsigned integer")));
 
             // Test case: limit = "10" should fail (string instead of integer)
             p[jss::limit] = "10";
-            BEAST_EXPECT(
-                env.rpc("json", "account_tx", to_string(p))[jss::result][jss::error_message] ==
-                rpc::expectedFieldMessage(jss::limit, "unsigned integer"));
+            BEAST_EXPECT(isErr(
+                env.rpc("json", "account_tx", to_string(p)),
+                RpcInvalidParams,
+                rpc::expectedFieldMessage(jss::limit, "unsigned integer")));
 
             // Test case: limit = true should fail (boolean instead of integer)
             p[jss::limit] = true;
-            BEAST_EXPECT(
-                env.rpc("json", "account_tx", to_string(p))[jss::result][jss::error_message] ==
-                rpc::expectedFieldMessage(jss::limit, "unsigned integer"));
+            BEAST_EXPECT(isErr(
+                env.rpc("json", "account_tx", to_string(p)),
+                RpcInvalidParams,
+                rpc::expectedFieldMessage(jss::limit, "unsigned integer")));
 
             // Test case: limit = false should fail (boolean instead of integer)
             p[jss::limit] = false;
-            BEAST_EXPECT(
-                env.rpc("json", "account_tx", to_string(p))[jss::result][jss::error_message] ==
-                rpc::expectedFieldMessage(jss::limit, "unsigned integer"));
+            BEAST_EXPECT(isErr(
+                env.rpc("json", "account_tx", to_string(p)),
+                RpcInvalidParams,
+                rpc::expectedFieldMessage(jss::limit, "unsigned integer")));
 
             // Test case: limit = -1 should fail (negative number)
             p[jss::limit] = -1;
-            BEAST_EXPECT(
-                env.rpc("json", "account_tx", to_string(p))[jss::result][jss::error_message] ==
-                rpc::expectedFieldMessage(jss::limit, "unsigned integer"));
+            BEAST_EXPECT(isErr(
+                env.rpc("json", "account_tx", to_string(p)),
+                RpcInvalidParams,
+                rpc::expectedFieldMessage(jss::limit, "unsigned integer")));
 
             // Test case: limit = [] should fail (array instead of integer)
             p[jss::limit] = json::Value(json::ValueType::Array);
-            BEAST_EXPECT(
-                env.rpc("json", "account_tx", to_string(p))[jss::result][jss::error_message] ==
-                rpc::expectedFieldMessage(jss::limit, "unsigned integer"));
+            BEAST_EXPECT(isErr(
+                env.rpc("json", "account_tx", to_string(p)),
+                RpcInvalidParams,
+                rpc::expectedFieldMessage(jss::limit, "unsigned integer")));
 
             // Test case: limit = {} should fail (object instead of integer)
             p[jss::limit] = json::Value(json::ValueType::Object);
-            BEAST_EXPECT(
-                env.rpc("json", "account_tx", to_string(p))[jss::result][jss::error_message] ==
-                rpc::expectedFieldMessage(jss::limit, "unsigned integer"));
+            BEAST_EXPECT(isErr(
+                env.rpc("json", "account_tx", to_string(p)),
+                RpcInvalidParams,
+                rpc::expectedFieldMessage(jss::limit, "unsigned integer")));
 
             // Test case: limit = "malformed" should fail (malformed string)
             p[jss::limit] = "malformed";
-            BEAST_EXPECT(
-                env.rpc("json", "account_tx", to_string(p))[jss::result][jss::error_message] ==
-                rpc::expectedFieldMessage(jss::limit, "unsigned integer"));
+            BEAST_EXPECT(isErr(
+                env.rpc("json", "account_tx", to_string(p)),
+                RpcInvalidParams,
+                rpc::expectedFieldMessage(jss::limit, "unsigned integer")));
 
             // Test case: limit = ["limit"] should fail (array with string)
             p[jss::limit] = json::Value(json::ValueType::Array);
             p[jss::limit].append("limit");
-            BEAST_EXPECT(
-                env.rpc("json", "account_tx", to_string(p))[jss::result][jss::error_message] ==
-                rpc::expectedFieldMessage(jss::limit, "unsigned integer"));
+            BEAST_EXPECT(isErr(
+                env.rpc("json", "account_tx", to_string(p)),
+                RpcInvalidParams,
+                rpc::expectedFieldMessage(jss::limit, "unsigned integer")));
 
             // Test case: limit = {"limit": 10} should fail (object with
             // property)
             p[jss::limit] = json::Value(json::ValueType::Object);
             p[jss::limit][jss::limit] = 10;
-            BEAST_EXPECT(
-                env.rpc("json", "account_tx", to_string(p))[jss::result][jss::error_message] ==
-                rpc::expectedFieldMessage(jss::limit, "unsigned integer"));
+            BEAST_EXPECT(isErr(
+                env.rpc("json", "account_tx", to_string(p)),
+                RpcInvalidParams,
+                rpc::expectedFieldMessage(jss::limit, "unsigned integer")));
 
             // Test case: limit = 10 should succeed (valid integer)
             p[jss::limit] = 10;
@@ -985,12 +1038,16 @@ class AccountTx_test : public beast::unit_test::Suite
         };
 
         auto const checkError = [&](json::Value const& delegateParams,
-                                    std::string const& errToken) {
+                                    std::string const& errToken,
+                                    ErrorCodeI code,
+                                    std::string const& errMessage) {
             json::Value params;
             params[jss::account] = alice.human();
             params[jss::delegate] = delegateParams;
             auto res = env.rpc("json", "account_tx", to_string(params));
             BEAST_EXPECT(res[jss::result][jss::error] == errToken);
+            BEAST_EXPECT(res[jss::result][jss::error_code] == code);
+            BEAST_EXPECT(res[jss::result][jss::error_message] == errMessage);
         };
 
         // Filter: Delegatee. Expects TX #2 (Signed by Bob)
@@ -1061,27 +1118,27 @@ class AccountTx_test : public beast::unit_test::Suite
         // "delegate" is not an object (e.g., string)
         {
             json::Value const p = "not_an_object";
-            checkError(p, "invalidParams");
+            checkError(p, "invalidParams", RpcInvalidParams, "Invalid field 'delegate'.");
         }
 
         // Missing "delegate_filter" inside object
         {
             json::Value const p(json::ValueType::Object);
-            checkError(p, "invalidParams");
+            checkError(p, "invalidParams", RpcInvalidParams, "Invalid field 'delegate_filter'.");
         }
 
         // "delegate_filter" is not a string (e.g., int)
         {
             json::Value p;
             p[jss::delegate_filter] = 123;
-            checkError(p, "invalidParams");
+            checkError(p, "invalidParams", RpcInvalidParams, "Invalid field 'delegate_filter'.");
         }
 
         // "delegate_filter" has invalid value
         {
             json::Value p;
             p[jss::delegate_filter] = "random_string";
-            checkError(p, "invalidParams");
+            checkError(p, "invalidParams", RpcInvalidParams, "Invalid field 'delegate_filter'.");
         }
 
         // "counterparty" is not a string
@@ -1089,7 +1146,7 @@ class AccountTx_test : public beast::unit_test::Suite
             json::Value p;
             p[jss::delegate_filter] = "actor";
             p[jss::counter_party] = 123;
-            checkError(p, "invalidParams");
+            checkError(p, "invalidParams", RpcInvalidParams, "Invalid field 'counter_party'.");
         }
 
         // "counterparty" is malformed base58
@@ -1097,7 +1154,7 @@ class AccountTx_test : public beast::unit_test::Suite
             json::Value p;
             p[jss::delegate_filter] = "actor";
             p[jss::counter_party] = "not_an_account";
-            checkError(p, "actMalformed");
+            checkError(p, "actMalformed", RpcActMalformed, "Account malformed.");
         }
 
         // Multi-signed non-delegated TX: Alice pays Carol via multi-sig.
@@ -1181,6 +1238,11 @@ class AccountTx_test : public beast::unit_test::Suite
                 p[jss::marker] = delegateMarker;
                 auto const r = env.rpc("json", "account_tx", to_string(p));
                 BEAST_EXPECT(r[jss::result][jss::error] == "invalidParams");
+                BEAST_EXPECT(r[jss::result][jss::error_code] == RpcInvalidParams);
+                BEAST_EXPECT(
+                    r[jss::result][jss::error_message] ==
+                    "Do not mix delegate and non-delegate pagination markers in account_tx; "
+                    "repeat the same `delegate` object when using a delegate marker.");
             }
 
             // Obtain a non-delegate marker; it must not carry the flag.
@@ -1205,6 +1267,11 @@ class AccountTx_test : public beast::unit_test::Suite
                 p[jss::marker] = normalMarker;
                 auto const r = env.rpc("json", "account_tx", to_string(p));
                 BEAST_EXPECT(r[jss::result][jss::error] == "invalidParams");
+                BEAST_EXPECT(r[jss::result][jss::error_code] == RpcInvalidParams);
+                BEAST_EXPECT(
+                    r[jss::result][jss::error_message] ==
+                    "Do not mix delegate and non-delegate pagination markers in account_tx; "
+                    "repeat the same `delegate` object when using a delegate marker.");
             }
         }
     }

src/test/rpc/AmendmentBlocked_test.cpp

@@ -14,6 +14,7 @@
 #include <xrpl/beast/unit_test/suite.h>
 #include <xrpl/config/Constants.h>
 #include <xrpl/json/to_string.h>
+#include <xrpl/protocol/ErrorCodes.h>
 #include <xrpl/protocol/KeyType.h>
 #include <xrpl/protocol/Serializer.h>
 #include <xrpl/protocol/jss.h>
@@ -186,32 +187,42 @@ class AmendmentBlocked_test : public beast::unit_test::Suite
 
         // ledger_accept
         jr = env.rpc("ledger_accept")[jss::result];
-        BEAST_EXPECT(jr.isMember(jss::error) && jr[jss::error] == "amendmentBlocked");
         BEAST_EXPECT(jr[jss::status] == "error");
+        BEAST_EXPECT(jr[jss::error] == "amendmentBlocked");
+        BEAST_EXPECT(jr[jss::error_code] == RpcAmendmentBlocked);
+        BEAST_EXPECT(jr[jss::error_message] == "Amendment blocked, need upgrade.");
         BEAST_EXPECT(!jr.isMember(jss::warnings));
 
         // ledger_current
         jr = env.rpc("ledger_current")[jss::result];
-        BEAST_EXPECT(jr.isMember(jss::error) && jr[jss::error] == "amendmentBlocked");
         BEAST_EXPECT(jr[jss::status] == "error");
+        BEAST_EXPECT(jr[jss::error] == "amendmentBlocked");
+        BEAST_EXPECT(jr[jss::error_code] == RpcAmendmentBlocked);
+        BEAST_EXPECT(jr[jss::error_message] == "Amendment blocked, need upgrade.");
         BEAST_EXPECT(!jr.isMember(jss::warnings));
 
         // owner_info
         jr = env.rpc("owner_info", alice.human())[jss::result];
-        BEAST_EXPECT(jr.isMember(jss::error) && jr[jss::error] == "amendmentBlocked");
         BEAST_EXPECT(jr[jss::status] == "error");
+        BEAST_EXPECT(jr[jss::error] == "amendmentBlocked");
+        BEAST_EXPECT(jr[jss::error_code] == RpcAmendmentBlocked);
+        BEAST_EXPECT(jr[jss::error_message] == "Amendment blocked, need upgrade.");
         BEAST_EXPECT(!jr.isMember(jss::warnings));
 
         // path_find
         jr = wsc->invoke("path_find", pfReq)[jss::result];
-        BEAST_EXPECT(jr.isMember(jss::error) && jr[jss::error] == "amendmentBlocked");
         BEAST_EXPECT(jr[jss::status] == "error");
+        BEAST_EXPECT(jr[jss::error] == "amendmentBlocked");
+        BEAST_EXPECT(jr[jss::error_code] == RpcAmendmentBlocked);
+        BEAST_EXPECT(jr[jss::error_message] == "Amendment blocked, need upgrade.");
         BEAST_EXPECT(!jr.isMember(jss::warnings));
 
         // submit
         jr = env.rpc("submit", strHex(s.slice()))[jss::result];
-        BEAST_EXPECT(jr.isMember(jss::error) && jr[jss::error] == "amendmentBlocked");
         BEAST_EXPECT(jr[jss::status] == "error");
+        BEAST_EXPECT(jr[jss::error] == "amendmentBlocked");
+        BEAST_EXPECT(jr[jss::error_code] == RpcAmendmentBlocked);
+        BEAST_EXPECT(jr[jss::error_message] == "Amendment blocked, need upgrade.");
         BEAST_EXPECT(!jr.isMember(jss::warnings));
 
         // submit_multisigned
@@ -221,7 +232,9 @@ class AmendmentBlocked_test : public beast::unit_test::Suite
         BEAST_EXPECT(jr[jss::status] == "success");
         msReq[jss::tx_json] = jr[jss::tx_json];
         jr = env.rpc("json", "submit_multisigned", to_string(msReq))[jss::result];
-        BEAST_EXPECT(jr.isMember(jss::error) && jr[jss::error] == "amendmentBlocked");
+        BEAST_EXPECT(jr[jss::error] == "amendmentBlocked");
+        BEAST_EXPECT(jr[jss::error_code] == RpcAmendmentBlocked);
+        BEAST_EXPECT(jr[jss::error_message] == "Amendment blocked, need upgrade.");
         BEAST_EXPECT(!jr.isMember(jss::warnings));
     }
 

src/test/rpc/BookChanges_test.cpp

@@ -19,6 +19,7 @@
 #include <xrpl/json/json_value.h>
 #include <xrpl/json/to_string.h>
 #include <xrpl/ledger/Ledger.h>
+#include <xrpl/protocol/ErrorCodes.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/LedgerFormats.h>
 #include <xrpl/protocol/SField.h>
@@ -77,8 +78,12 @@ public:
         // non-conventional ledger input should throw an error
         params["ledger"] = "non_conventional_ledger_input";
         resp = env.rpc("json", "book_changes", to_string(params));
-        BEAST_EXPECT(resp[jss::result].isMember(jss::error));
-        BEAST_EXPECT(resp[jss::result][jss::status] != "success");
+        BEAST_EXPECT(resp[jss::result][jss::status] == "error");
+        BEAST_EXPECT(resp[jss::result][jss::error] == "invalidParams");
+        BEAST_EXPECT(resp[jss::result][jss::error_code] == RpcInvalidParams);
+        BEAST_EXPECT(
+            resp[jss::result][jss::error_message] ==
+            "Invalid field 'ledger', not string or number.");
     }
 
     void

src/test/rpc/Book_test.cpp

@@ -20,6 +20,7 @@
 #include <xrpl/json/to_string.h>
 #include <xrpl/ledger/helpers/DirectoryHelpers.h>
 #include <xrpl/protocol/AccountID.h>
+#include <xrpl/protocol/ErrorCodes.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/Indexes.h>
 #include <xrpl/protocol/Issue.h>
@@ -1225,6 +1226,7 @@ public:
             jvParams[jss::ledger_index] = 10u;
             auto const jrr = env.rpc("json", "book_offers", to_string(jvParams))[jss::result];
             BEAST_EXPECT(jrr[jss::error] == "lgrNotFound");
+            BEAST_EXPECT(jrr[jss::error_code] == RpcLgrNotFound);
             BEAST_EXPECT(jrr[jss::error_message] == "ledgerNotFound");
         }
 
@@ -1233,6 +1235,7 @@ public:
             jvParams[jss::ledger_index] = "validated";
             auto const jrr = env.rpc("json", "book_offers", to_string(jvParams))[jss::result];
             BEAST_EXPECT(jrr[jss::error] == "invalidParams");
+            BEAST_EXPECT(jrr[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(jrr[jss::error_message] == "Missing field 'taker_pays'.");
         }
 
@@ -1242,6 +1245,7 @@ public:
             jvParams[jss::taker_pays] = json::ValueType::Object;
             auto const jrr = env.rpc("json", "book_offers", to_string(jvParams))[jss::result];
             BEAST_EXPECT(jrr[jss::error] == "invalidParams");
+            BEAST_EXPECT(jrr[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(jrr[jss::error_message] == "Missing field 'taker_gets'.");
         }
 
@@ -1252,6 +1256,7 @@ public:
             jvParams[jss::taker_gets] = json::ValueType::Object;
             auto const jrr = env.rpc("json", "book_offers", to_string(jvParams))[jss::result];
             BEAST_EXPECT(jrr[jss::error] == "invalidParams");
+            BEAST_EXPECT(jrr[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(jrr[jss::error_message] == "Invalid field 'taker_pays', not object.");
         }
 
@@ -1262,6 +1267,7 @@ public:
             jvParams[jss::taker_gets] = "not an object";
             auto const jrr = env.rpc("json", "book_offers", to_string(jvParams))[jss::result];
             BEAST_EXPECT(jrr[jss::error] == "invalidParams");
+            BEAST_EXPECT(jrr[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(jrr[jss::error_message] == "Invalid field 'taker_gets', not object.");
         }
 
@@ -1272,6 +1278,7 @@ public:
             jvParams[jss::taker_gets] = json::ValueType::Object;
             auto const jrr = env.rpc("json", "book_offers", to_string(jvParams))[jss::result];
             BEAST_EXPECT(jrr[jss::error] == "invalidParams");
+            BEAST_EXPECT(jrr[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(jrr[jss::error_message] == "Missing field 'taker_pays.currency'.");
         }
 
@@ -1282,6 +1289,7 @@ public:
             jvParams[jss::taker_gets] = json::ValueType::Object;
             auto const jrr = env.rpc("json", "book_offers", to_string(jvParams))[jss::result];
             BEAST_EXPECT(jrr[jss::error] == "invalidParams");
+            BEAST_EXPECT(jrr[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(
                 jrr[jss::error_message] == "Invalid field 'taker_pays.currency', not string.");
         }
@@ -1293,6 +1301,7 @@ public:
             jvParams[jss::taker_gets] = json::ValueType::Object;
             auto const jrr = env.rpc("json", "book_offers", to_string(jvParams))[jss::result];
             BEAST_EXPECT(jrr[jss::error] == "invalidParams");
+            BEAST_EXPECT(jrr[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(jrr[jss::error_message] == "Missing field 'taker_gets.currency'.");
         }
 
@@ -1303,6 +1312,7 @@ public:
             jvParams[jss::taker_gets][jss::currency] = 1;
             auto const jrr = env.rpc("json", "book_offers", to_string(jvParams))[jss::result];
             BEAST_EXPECT(jrr[jss::error] == "invalidParams");
+            BEAST_EXPECT(jrr[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(
                 jrr[jss::error_message] == "Invalid field 'taker_gets.currency', not string.");
         }
@@ -1314,6 +1324,7 @@ public:
             jvParams[jss::taker_gets][jss::currency] = "XRP";
             auto const jrr = env.rpc("json", "book_offers", to_string(jvParams))[jss::result];
             BEAST_EXPECT(jrr[jss::error] == "srcCurMalformed");
+            BEAST_EXPECT(jrr[jss::error_code] == RpcSrcCurMalformed);
             BEAST_EXPECT(
                 jrr[jss::error_message] == "Invalid field 'taker_pays.currency', bad currency.");
         }
@@ -1325,6 +1336,7 @@ public:
             jvParams[jss::taker_gets][jss::currency] = "NOT_VALID";
             auto const jrr = env.rpc("json", "book_offers", to_string(jvParams))[jss::result];
             BEAST_EXPECT(jrr[jss::error] == "dstAmtMalformed");
+            BEAST_EXPECT(jrr[jss::error_code] == RpcDstAmtMalformed);
             BEAST_EXPECT(
                 jrr[jss::error_message] == "Invalid field 'taker_gets.currency', bad currency.");
         }
@@ -1337,6 +1349,7 @@ public:
             jvParams[jss::taker_gets][jss::issuer] = 1;
             auto const jrr = env.rpc("json", "book_offers", to_string(jvParams))[jss::result];
             BEAST_EXPECT(jrr[jss::error] == "invalidParams");
+            BEAST_EXPECT(jrr[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(
                 jrr[jss::error_message] == "Invalid field 'taker_gets.issuer', not string.");
         }
@@ -1349,6 +1362,7 @@ public:
             jvParams[jss::taker_gets][jss::currency] = "USD";
             auto const jrr = env.rpc("json", "book_offers", to_string(jvParams))[jss::result];
             BEAST_EXPECT(jrr[jss::error] == "invalidParams");
+            BEAST_EXPECT(jrr[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(
                 jrr[jss::error_message] == "Invalid field 'taker_pays.issuer', not string.");
         }
@@ -1361,6 +1375,7 @@ public:
             jvParams[jss::taker_gets][jss::currency] = "USD";
             auto const jrr = env.rpc("json", "book_offers", to_string(jvParams))[jss::result];
             BEAST_EXPECT(jrr[jss::error] == "srcIsrMalformed");
+            BEAST_EXPECT(jrr[jss::error_code] == RpcSrcIsrMalformed);
             BEAST_EXPECT(
                 jrr[jss::error_message] == "Invalid field 'taker_pays.issuer', bad issuer.");
         }
@@ -1373,6 +1388,7 @@ public:
             jvParams[jss::taker_gets][jss::currency] = "USD";
             auto const jrr = env.rpc("json", "book_offers", to_string(jvParams))[jss::result];
             BEAST_EXPECT(jrr[jss::error] == "srcIsrMalformed");
+            BEAST_EXPECT(jrr[jss::error_code] == RpcSrcIsrMalformed);
             BEAST_EXPECT(
                 jrr[jss::error_message] ==
                 "Invalid field 'taker_pays.issuer', bad issuer account one.");
@@ -1386,6 +1402,7 @@ public:
             jvParams[jss::taker_gets][jss::issuer] = gw.human() + "DEAD";
             auto const jrr = env.rpc("json", "book_offers", to_string(jvParams))[jss::result];
             BEAST_EXPECT(jrr[jss::error] == "dstIsrMalformed");
+            BEAST_EXPECT(jrr[jss::error_code] == RpcDstIsrMalformed);
             BEAST_EXPECT(
                 jrr[jss::error_message] == "Invalid field 'taker_gets.issuer', bad issuer.");
         }
@@ -1398,6 +1415,7 @@ public:
             jvParams[jss::taker_gets][jss::issuer] = toBase58(noAccount());
             auto const jrr = env.rpc("json", "book_offers", to_string(jvParams))[jss::result];
             BEAST_EXPECT(jrr[jss::error] == "dstIsrMalformed");
+            BEAST_EXPECT(jrr[jss::error_code] == RpcDstIsrMalformed);
             BEAST_EXPECT(
                 jrr[jss::error_message] ==
                 "Invalid field 'taker_gets.issuer', bad issuer account one.");
@@ -1412,6 +1430,7 @@ public:
             jvParams[jss::taker_gets][jss::issuer] = gw.human();
             auto const jrr = env.rpc("json", "book_offers", to_string(jvParams))[jss::result];
             BEAST_EXPECT(jrr[jss::error] == "srcIsrMalformed");
+            BEAST_EXPECT(jrr[jss::error_code] == RpcSrcIsrMalformed);
             BEAST_EXPECT(
                 jrr[jss::error_message] ==
                 "Unneeded field 'taker_pays.issuer' "
@@ -1427,6 +1446,7 @@ public:
             jvParams[jss::taker_gets][jss::issuer] = gw.human();
             auto const jrr = env.rpc("json", "book_offers", to_string(jvParams))[jss::result];
             BEAST_EXPECT(jrr[jss::error] == "srcIsrMalformed");
+            BEAST_EXPECT(jrr[jss::error_code] == RpcSrcIsrMalformed);
             BEAST_EXPECT(
                 jrr[jss::error_message] ==
                 "Invalid field 'taker_pays.issuer', expected non-XRP issuer.");
@@ -1441,6 +1461,7 @@ public:
             jvParams[jss::taker_gets][jss::issuer] = gw.human();
             auto const jrr = env.rpc("json", "book_offers", to_string(jvParams))[jss::result];
             BEAST_EXPECT(jrr[jss::error] == "invalidParams");
+            BEAST_EXPECT(jrr[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(jrr[jss::error_message] == "Invalid field 'taker', not string.");
         }
 
@@ -1453,6 +1474,7 @@ public:
             jvParams[jss::taker_gets][jss::issuer] = gw.human();
             auto const jrr = env.rpc("json", "book_offers", to_string(jvParams))[jss::result];
             BEAST_EXPECT(jrr[jss::error] == "invalidParams");
+            BEAST_EXPECT(jrr[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(jrr[jss::error_message] == "Invalid field 'taker'.");
         }
 
@@ -1466,6 +1488,7 @@ public:
             jvParams[jss::taker_gets][jss::issuer] = gw.human();
             auto const jrr = env.rpc("json", "book_offers", to_string(jvParams))[jss::result];
             BEAST_EXPECT(jrr[jss::error] == "badMarket");
+            BEAST_EXPECT(jrr[jss::error_code] == RpcBadMarket);
             BEAST_EXPECT(jrr[jss::error_message] == "No such market.");
         }
 
@@ -1479,6 +1502,7 @@ public:
             jvParams[jss::taker_gets][jss::issuer] = gw.human();
             auto const jrr = env.rpc("json", "book_offers", to_string(jvParams))[jss::result];
             BEAST_EXPECT(jrr[jss::error] == "invalidParams");
+            BEAST_EXPECT(jrr[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(jrr[jss::error_message] == "Invalid field 'limit', not unsigned integer.");
         }
 
@@ -1492,6 +1516,7 @@ public:
             jvParams[jss::taker_gets][jss::issuer] = gw.human();
             auto const jrr = env.rpc("json", "book_offers", to_string(jvParams))[jss::result];
             BEAST_EXPECT(jrr[jss::error] == "invalidParams");
+            BEAST_EXPECT(jrr[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(jrr[jss::error_message] == "Invalid field 'limit'.");
         }
 
@@ -1503,6 +1528,7 @@ public:
             jvParams[jss::taker_gets][jss::currency] = "USD";
             auto const jrr = env.rpc("json", "book_offers", to_string(jvParams))[jss::result];
             BEAST_EXPECT(jrr[jss::error] == "dstIsrMalformed");
+            BEAST_EXPECT(jrr[jss::error_code] == RpcDstIsrMalformed);
             BEAST_EXPECT(
                 jrr[jss::error_message] ==
                 "Invalid field 'taker_gets.issuer', "
@@ -1518,6 +1544,7 @@ public:
             jvParams[jss::taker_gets][jss::issuer] = gw.human();
             auto const jrr = env.rpc("json", "book_offers", to_string(jvParams))[jss::result];
             BEAST_EXPECT(jrr[jss::error] == "dstIsrMalformed");
+            BEAST_EXPECT(jrr[jss::error_code] == RpcDstIsrMalformed);
             BEAST_EXPECT(
                 jrr[jss::error_message] ==
                 "Unneeded field 'taker_gets.issuer' "
@@ -1533,6 +1560,7 @@ public:
             jvParams[jss::domain] = "badString";
             auto const jrr = env.rpc("json", "book_offers", to_string(jvParams))[jss::result];
             BEAST_EXPECT(jrr[jss::error] == "domainMalformed");
+            BEAST_EXPECT(jrr[jss::error_code] == RpcDomainMalformed);
             BEAST_EXPECT(jrr[jss::error_message] == "Unable to parse domain.");
         }
     }

src/test/rpc/Connect_test.cpp

@@ -2,6 +2,7 @@
 #include <test/jtx/Env.h>
 
 #include <xrpl/beast/unit_test/suite.h>
+#include <xrpl/protocol/ErrorCodes.h>
 #include <xrpl/protocol/jss.h>
 
 namespace xrpl {
@@ -22,8 +23,8 @@ class Connect_test : public beast::unit_test::Suite
 
             auto const result = env.rpc("json", "connect", "{}");
             BEAST_EXPECT(result[jss::result][jss::status] == "error");
-            BEAST_EXPECT(result[jss::result].isMember(jss::error));
             BEAST_EXPECT(result[jss::result][jss::error] == "notSynced");
+            BEAST_EXPECT(result[jss::result][jss::error_code] == RpcNotSynced);
             BEAST_EXPECT(result[jss::result][jss::error_message] == "Not synced to the network.");
         }
     }

src/test/rpc/DepositAuthorized_test.cpp

@@ -8,6 +8,7 @@
 
 #include <xrpl/beast/unit_test/suite.h>
 #include <xrpl/json/json_value.h>
+#include <xrpl/protocol/ErrorCodes.h>
 #include <xrpl/protocol/Protocol.h>  // IWYU pragma: keep
 #include <xrpl/protocol/SField.h>
 #include <xrpl/protocol/TxFlags.h>
@@ -154,12 +155,16 @@ public:
         Account const becky{"becky"};
 
         // Lambda that checks the (error) result of deposit_authorized.
-        auto const verifyErr =
-            [this](json::Value const& result, char const* error, char const* errorMsg) {
-                BEAST_EXPECT(result[jss::result][jss::status] == jss::error);
-                BEAST_EXPECT(result[jss::result][jss::error] == error);
-                BEAST_EXPECT(result[jss::result][jss::error_message] == errorMsg);
-            };
+        auto const verifyErr = [this](
+                                   json::Value const& result,
+                                   char const* error,
+                                   ErrorCodeI code,
+                                   char const* errorMsg) {
+            BEAST_EXPECT(result[jss::result][jss::status] == jss::error);
+            BEAST_EXPECT(result[jss::result][jss::error] == error);
+            BEAST_EXPECT(result[jss::result][jss::error_code] == code);
+            BEAST_EXPECT(result[jss::result][jss::error_message] == errorMsg);
+        };
 
         Env env(*this);
         {
@@ -167,28 +172,33 @@ public:
             json::Value args{depositAuthArgs(alice, becky)};
             args.removeMember(jss::source_account);
             json::Value const result{env.rpc("json", "deposit_authorized", args.toStyledString())};
-            verifyErr(result, "invalidParams", "Missing field 'source_account'.");
+            verifyErr(result, "invalidParams", RpcInvalidParams, "Missing field 'source_account'.");
         }
         {
             // Non-string source_account field.
             json::Value args{depositAuthArgs(alice, becky)};
             args[jss::source_account] = 7.3;
             json::Value const result{env.rpc("json", "deposit_authorized", args.toStyledString())};
-            verifyErr(result, "invalidParams", "Invalid field 'source_account', not a string.");
+            verifyErr(
+                result,
+                "invalidParams",
+                RpcInvalidParams,
+                "Invalid field 'source_account', not a string.");
         }
         {
             // Corrupt source_account field.
             json::Value args{depositAuthArgs(alice, becky)};
             args[jss::source_account] = "rG1QQv2nh2gr7RCZ!P8YYcBUKCCN633jCn";
             json::Value const result{env.rpc("json", "deposit_authorized", args.toStyledString())};
-            verifyErr(result, "actMalformed", "Account malformed.");
+            verifyErr(result, "actMalformed", RpcActMalformed, "Account malformed.");
         }
         {
             // Missing destination_account field.
             json::Value args{depositAuthArgs(alice, becky)};
             args.removeMember(jss::destination_account);
             json::Value const result{env.rpc("json", "deposit_authorized", args.toStyledString())};
-            verifyErr(result, "invalidParams", "Missing field 'destination_account'.");
+            verifyErr(
+                result, "invalidParams", RpcInvalidParams, "Missing field 'destination_account'.");
         }
         {
             // Non-string destination_account field.
@@ -196,40 +206,46 @@ public:
             args[jss::destination_account] = 7.3;
             json::Value const result{env.rpc("json", "deposit_authorized", args.toStyledString())};
             verifyErr(
-                result, "invalidParams", "Invalid field 'destination_account', not a string.");
+                result,
+                "invalidParams",
+                RpcInvalidParams,
+                "Invalid field 'destination_account', not a string.");
         }
         {
             // Corrupt destination_account field.
             json::Value args{depositAuthArgs(alice, becky)};
             args[jss::destination_account] = "rP6P9ypfAmc!pw8SZHNwM4nvZHFXDraQas";
             json::Value const result{env.rpc("json", "deposit_authorized", args.toStyledString())};
-            verifyErr(result, "actMalformed", "Account malformed.");
+            verifyErr(result, "actMalformed", RpcActMalformed, "Account malformed.");
         }
         {
             // Request an invalid ledger.
             json::Value const args{depositAuthArgs(alice, becky, "-1")};
             json::Value const result{env.rpc("json", "deposit_authorized", args.toStyledString())};
             verifyErr(
-                result, "invalidParams", "Invalid field 'ledger_index', not string or number.");
+                result,
+                "invalidParams",
+                RpcInvalidParams,
+                "Invalid field 'ledger_index', not string or number.");
         }
         {
             // Request a ledger that doesn't exist yet as a string.
             json::Value const args{depositAuthArgs(alice, becky, "17")};
             json::Value const result{env.rpc("json", "deposit_authorized", args.toStyledString())};
-            verifyErr(result, "lgrNotFound", "ledgerNotFound");
+            verifyErr(result, "lgrNotFound", RpcLgrNotFound, "ledgerNotFound");
         }
         {
             // Request a ledger that doesn't exist yet.
             json::Value args{depositAuthArgs(alice, becky)};
             args[jss::ledger_index] = 17;
             json::Value const result{env.rpc("json", "deposit_authorized", args.toStyledString())};
-            verifyErr(result, "lgrNotFound", "ledgerNotFound");
+            verifyErr(result, "lgrNotFound", RpcLgrNotFound, "ledgerNotFound");
         }
         {
             // alice is not yet funded.
             json::Value const args{depositAuthArgs(alice, becky)};
             json::Value const result{env.rpc("json", "deposit_authorized", args.toStyledString())};
-            verifyErr(result, "srcActNotFound", "Source account not found.");
+            verifyErr(result, "srcActNotFound", RpcSrcActNotFound, "Source account not found.");
         }
         env.fund(XRP(1000), alice);
         env.close();
@@ -237,7 +253,8 @@ public:
             // becky is not yet funded.
             json::Value const args{depositAuthArgs(alice, becky)};
             json::Value const result{env.rpc("json", "deposit_authorized", args.toStyledString())};
-            verifyErr(result, "dstActNotFound", "Destination account not found.");
+            verifyErr(
+                result, "dstActNotFound", RpcDstActNotFound, "Destination account not found.");
         }
         env.fund(XRP(1000), becky);
         env.close();
@@ -256,9 +273,11 @@ public:
         jtx::Account const& dst,
         bool authorized,
         std::vector<std::string> credentialIDs = {},
-        std::string_view error = "")
+        std::string_view error = "",
+        ErrorCodeI code = RpcSuccess,
+        std::string_view errorMessage = "")
     {
-        BEAST_EXPECT(result[jss::status] == authorized ? jss::success : jss::error);
+        BEAST_EXPECT(result[jss::status] == (authorized ? jss::success : jss::error));
         if (result.isMember(jss::deposit_authorized))
             BEAST_EXPECT(result[jss::deposit_authorized] == authorized);
         if (authorized)
@@ -270,7 +289,11 @@ public:
 
         BEAST_EXPECT(result.isMember(jss::error) == !error.empty());
         if (!error.empty())
+        {
             BEAST_EXPECT(result[jss::error].asString() == error);
+            BEAST_EXPECT(result[jss::error_code] == code);
+            BEAST_EXPECT(result[jss::error_message].asString() == errorMessage);
+        }
 
         if (authorized)
         {
@@ -334,7 +357,15 @@ public:
             args[jss::credentials] = json::ValueType::Array;
 
             auto const jv = env.rpc("json", "deposit_authorized", args.toStyledString());
-            checkCredentialsResponse(jv[jss::result], alice, becky, false, {}, "invalidParams");
+            checkCredentialsResponse(
+                jv[jss::result],
+                alice,
+                becky,
+                false,
+                {},
+                "invalidParams",
+                RpcInvalidParams,
+                "Invalid field 'credentials', not is non-empty array of CredentialID(hash256).");
         }
 
         {
@@ -348,7 +379,15 @@ public:
             args[jss::credentials].append(3);
 
             auto const jv = env.rpc("json", "deposit_authorized", args.toStyledString());
-            checkCredentialsResponse(jv[jss::result], alice, becky, false, {}, "invalidParams");
+            checkCredentialsResponse(
+                jv[jss::result],
+                alice,
+                becky,
+                false,
+                {},
+                "invalidParams",
+                RpcInvalidParams,
+                "Invalid field 'credentials', not an array of CredentialID(hash256).");
         }
 
         {
@@ -362,7 +401,14 @@ public:
 
             auto const jv = env.rpc("json", "deposit_authorized", args.toStyledString());
             checkCredentialsResponse(
-                jv[jss::result], alice, becky, false, {"hello world"}, "invalidParams");
+                jv[jss::result],
+                alice,
+                becky,
+                false,
+                {"hello world"},
+                "invalidParams",
+                RpcInvalidParams,
+                "Invalid field 'credentials', not an array of CredentialID(hash256).");
         }
 
         {
@@ -389,7 +435,9 @@ public:
                     "0127AB8B4B29CCDBB61AA51C0799A8A6BB80B86A9899807C11ED576AF8516"
                     "473",
                 },
-                "badCredentials");
+                "badCredentials",
+                RpcBadCredentials,
+                "credentials don't exist");
         }
 
         {
@@ -403,7 +451,14 @@ public:
 
                 auto const jv = env.rpc("json", "deposit_authorized", args.toStyledString());
                 checkCredentialsResponse(
-                    jv[jss::result], alice, becky, false, {zero}, "badCredentials");
+                    jv[jss::result],
+                    alice,
+                    becky,
+                    false,
+                    {zero},
+                    "badCredentials",
+                    RpcBadCredentials,
+                    "credentials don't exist");
             }
         }
 
@@ -416,7 +471,14 @@ public:
                 "deposit_authorized",
                 depositAuthArgs(alice, becky, "validated", {credIdx}).toStyledString());
             checkCredentialsResponse(
-                jv[jss::result], alice, becky, false, {credIdx}, "badCredentials");
+                jv[jss::result],
+                alice,
+                becky,
+                false,
+                {credIdx},
+                "badCredentials",
+                RpcBadCredentials,
+                "credentials aren't accepted");
         }
 
         // alice accept credentials
@@ -430,7 +492,14 @@ public:
                 "deposit_authorized",
                 depositAuthArgs(alice, becky, "validated", {credIdx, credIdx}).toStyledString());
             checkCredentialsResponse(
-                jv[jss::result], alice, becky, false, {credIdx, credIdx}, "badCredentials");
+                jv[jss::result],
+                alice,
+                becky,
+                false,
+                {credIdx, credIdx},
+                "badCredentials",
+                RpcBadCredentials,
+                "duplicates in credentials");
         }
 
         {
@@ -453,7 +522,14 @@ public:
                 "deposit_authorized",
                 depositAuthArgs(alice, becky, "validated", kCredIds).toStyledString());
             checkCredentialsResponse(
-                jv[jss::result], alice, becky, false, kCredIds, "invalidParams");
+                jv[jss::result],
+                alice,
+                becky,
+                false,
+                kCredIds,
+                "invalidParams",
+                RpcInvalidParams,
+                "Invalid field 'credentials', not array too long.");
         }
 
         {
@@ -500,7 +576,14 @@ public:
                 "deposit_authorized",
                 depositAuthArgs(becky, alice, "validated", {credDiana}).toStyledString());
             checkCredentialsResponse(
-                jv[jss::result], becky, alice, false, {credDiana}, "badCredentials");
+                jv[jss::result],
+                becky,
+                alice,
+                false,
+                {credDiana},
+                "badCredentials",
+                RpcBadCredentials,
+                "credentials doesn't belong to the root account");
         }
 
         {
@@ -549,7 +632,14 @@ public:
                     depositAuthArgs(alice, becky, "validated", {credIdx2}).toStyledString());
 
                 checkCredentialsResponse(
-                    jv[jss::result], alice, becky, false, {credIdx2}, "badCredentials");
+                    jv[jss::result],
+                    alice,
+                    becky,
+                    false,
+                    {credIdx2},
+                    "badCredentials",
+                    RpcBadCredentials,
+                    "credentials are expired");
             }
         }
     }

src/test/rpc/Feature_test.cpp

@@ -11,6 +11,7 @@
 #include <xrpl/json/to_string.h>
 #include <xrpl/ledger/AmendmentTable.h>
 #include <xrpl/ledger/View.h>
+#include <xrpl/protocol/ErrorCodes.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/digest.h>
 #include <xrpl/protocol/jss.h>
@@ -206,6 +207,7 @@ class Feature_test : public beast::unit_test::Suite
         // feature names are case-sensitive - expect error here
         jrr = env.rpc("feature", "fMM")[jss::result];
         BEAST_EXPECT(jrr[jss::error] == "badFeature");
+        BEAST_EXPECT(jrr[jss::error_code] == RpcBadFeature);
         BEAST_EXPECT(jrr[jss::error_message] == "Feature unknown or invalid.");
 
         // Test feature name size checks
@@ -253,6 +255,7 @@ class Feature_test : public beast::unit_test::Suite
             params[jss::feature] = param;
             auto jrr = env.rpc("json", "feature", to_string(params))[jss::result];
             BEAST_EXPECT(jrr[jss::error] == "invalidParams");
+            BEAST_EXPECT(jrr[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(jrr[jss::error_message] == "Invalid parameters.");
         };
 
@@ -266,6 +269,7 @@ class Feature_test : public beast::unit_test::Suite
         {
             auto jrr = env.rpc("feature", "AllTheThings")[jss::result];
             BEAST_EXPECT(jrr[jss::error] == "badFeature");
+            BEAST_EXPECT(jrr[jss::error_code] == RpcBadFeature);
             BEAST_EXPECT(jrr[jss::error_message] == "Feature unknown or invalid.");
         }
     }
@@ -320,6 +324,7 @@ class Feature_test : public beast::unit_test::Suite
                 "EF";
             auto const result = env.rpc("json", "feature", to_string(params))[jss::result];
             BEAST_EXPECTS(result[jss::error] == "badFeature", result.toStyledString());
+            BEAST_EXPECT(result[jss::error_code] == RpcBadFeature);
             BEAST_EXPECT(result[jss::error_message] == "Feature unknown or invalid.");
         }
 
@@ -332,6 +337,7 @@ class Feature_test : public beast::unit_test::Suite
             params[jss::vetoed] = true;
             auto const result = env.rpc("json", "feature", to_string(params))[jss::result];
             BEAST_EXPECTS(result[jss::error] == "noPermission", result[jss::error].asString());
+            BEAST_EXPECT(result[jss::error_code] == RpcNoPermission);
             BEAST_EXPECT(
                 result[jss::error_message] == "You don't have permission for this command.");
         }
@@ -513,6 +519,7 @@ class Feature_test : public beast::unit_test::Suite
 
             auto const result = env.rpc("json", "feature", to_string(params))[jss::result];
             BEAST_EXPECT(result[jss::error] == "invalidParams");
+            BEAST_EXPECT(result[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(result[jss::error_message] == "Invalid parameters.");
         };
 
@@ -521,6 +528,7 @@ class Feature_test : public beast::unit_test::Suite
         // anything other than accept or reject is an error
         jrr = env.rpc("feature", kFeatureName, "maybe");
         BEAST_EXPECT(jrr[jss::error] == "invalidParams");
+        BEAST_EXPECT(jrr[jss::error_code] == RpcInvalidParams);
         BEAST_EXPECT(jrr[jss::error_message] == "Invalid parameters.");
     }
 
@@ -584,6 +592,7 @@ class Feature_test : public beast::unit_test::Suite
         // anything other than accept or reject is an error
         jrr = env.rpc("feature", featureName, "maybe");
         BEAST_EXPECT(jrr[jss::error] == "invalidParams");
+        BEAST_EXPECT(jrr[jss::error_code] == RpcInvalidParams);
         BEAST_EXPECT(jrr[jss::error_message] == "Invalid parameters.");
     }
 

src/test/rpc/GatewayBalances_test.cpp

@@ -10,6 +10,7 @@
 #include <xrpl/beast/unit_test/suite.h>
 #include <xrpl/json/json_value.h>
 #include <xrpl/protocol/ApiVersion.h>
+#include <xrpl/protocol/ErrorCodes.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/STAmount.h>
 #include <xrpl/protocol/TxFlags.h>
@@ -172,7 +173,12 @@ public:
 
             auto response = jv[jss::result];
             auto const error = apiVersion < 2u ? "invalidHotWallet" : "invalidParams";
+            auto const errorCode = apiVersion < 2u ? RpcInvalidHotwallet : RpcInvalidParams;
+            auto const errorMessage =
+                apiVersion < 2u ? "Invalid hotwallet." : "Invalid parameters.";
             BEAST_EXPECT(response[jss::error] == error);
+            BEAST_EXPECT(response[jss::error_code] == errorCode);
+            BEAST_EXPECT(response[jss::error_message] == errorMessage);
         });
     }
 
@@ -201,6 +207,8 @@ public:
             auto jv = wsc->invoke("gateway_balances", qry);
             expect(jv[jss::status] == "error");
             BEAST_EXPECT(jv[jss::result][jss::error] == "invalidParams");
+            BEAST_EXPECT(jv[jss::result][jss::error_code] == RpcInvalidParams);
+            BEAST_EXPECT(jv[jss::result][jss::error_message] == "Invalid field 'account'.");
         });
 
         // The same applies to a non-string "ident".
@@ -212,6 +220,8 @@ public:
             auto jv = wsc->invoke("gateway_balances", qry2);
             expect(jv[jss::status] == "error");
             BEAST_EXPECT(jv[jss::result][jss::error] == "invalidParams");
+            BEAST_EXPECT(jv[jss::result][jss::error_code] == RpcInvalidParams);
+            BEAST_EXPECT(jv[jss::result][jss::error_message] == "Invalid field 'ident'.");
         });
     }
 

src/test/rpc/GetAggregatePrice_test.cpp

@@ -12,6 +12,7 @@
 #include <xrpl/beast/utility/Journal.h>
 #include <xrpl/core/ServiceRegistry.h>
 #include <xrpl/ledger/OpenView.h>
+#include <xrpl/protocol/ErrorCodes.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/Indexes.h>
 #include <xrpl/protocol/SField.h>
@@ -42,10 +43,14 @@ public:
             auto const baseFee = env.current()->fees().base;
             // missing base_asset
             auto ret = Oracle::aggregatePrice(env, std::nullopt, "USD", kOracles);
+            BEAST_EXPECT(ret[jss::error].asString() == "invalidParams");
+            BEAST_EXPECT(ret[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(ret[jss::error_message].asString() == "Missing field 'base_asset'.");
 
             // missing quote_asset
             ret = Oracle::aggregatePrice(env, "XRP", std::nullopt, kOracles);
+            BEAST_EXPECT(ret[jss::error].asString() == "invalidParams");
+            BEAST_EXPECT(ret[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(ret[jss::error_message].asString() == "Missing field 'quote_asset'.");
 
             // invalid base_asset, quote_asset
@@ -69,28 +74,44 @@ public:
             {
                 ret = Oracle::aggregatePrice(env, "USD", v, kOracles);
                 BEAST_EXPECT(ret[jss::error].asString() == "invalidParams");
+                BEAST_EXPECT(ret[jss::error_code] == RpcInvalidParams);
+                BEAST_EXPECT(ret[jss::error_message].asString() == "Invalid parameters.");
                 ret = Oracle::aggregatePrice(env, v, "USD", kOracles);
                 BEAST_EXPECT(ret[jss::error].asString() == "invalidParams");
+                BEAST_EXPECT(ret[jss::error_code] == RpcInvalidParams);
+                BEAST_EXPECT(ret[jss::error_message].asString() == "Invalid parameters.");
                 ret = Oracle::aggregatePrice(env, v, v, kOracles);
                 BEAST_EXPECT(ret[jss::error].asString() == "invalidParams");
+                BEAST_EXPECT(ret[jss::error_code] == RpcInvalidParams);
+                BEAST_EXPECT(ret[jss::error_message].asString() == "Invalid parameters.");
             }
 
             // missing oracles array
             ret = Oracle::aggregatePrice(env, "XRP", "USD");
+            BEAST_EXPECT(ret[jss::error].asString() == "invalidParams");
+            BEAST_EXPECT(ret[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(ret[jss::error_message].asString() == "Missing field 'oracles'.");
 
             // empty oracles array
             ret = Oracle::aggregatePrice(env, "XRP", "USD", OraclesData{});
             BEAST_EXPECT(ret[jss::error].asString() == "oracleMalformed");
+            BEAST_EXPECT(ret[jss::error_code] == RpcOracleMalformed);
+            BEAST_EXPECT(ret[jss::error_message].asString() == "Oracle request is malformed.");
 
             // no token pairs found
             ret = Oracle::aggregatePrice(env, "YAN", "USD", kOracles);
             BEAST_EXPECT(ret[jss::error].asString() == "objectNotFound");
+            BEAST_EXPECT(ret[jss::error_code] == RpcObjectNotFound);
+            BEAST_EXPECT(
+                ret[jss::error_message].asString() == "The requested object was not found.");
 
             // invalid oracle document id
             // id doesn't exist
             ret = Oracle::aggregatePrice(env, "XRP", "USD", {{{owner, 2}}});
             BEAST_EXPECT(ret[jss::error].asString() == "objectNotFound");
+            BEAST_EXPECT(ret[jss::error_code] == RpcObjectNotFound);
+            BEAST_EXPECT(
+                ret[jss::error_message].asString() == "The requested object was not found.");
             // invalid values
             std::vector<AnyValue> const invalidDocument = {kNoneTag, 1.2, -1, "", "none", "1.2"};
             for (auto const& v : invalidDocument)
@@ -99,17 +120,26 @@ public:
                 json::Value jv;
                 toJson(jv, v);
                 BEAST_EXPECT(ret[jss::error].asString() == "invalidParams");
+                BEAST_EXPECT(ret[jss::error_code] == RpcInvalidParams);
+                BEAST_EXPECT(ret[jss::error_message].asString() == "Invalid parameters.");
             }
             // missing document id
             ret = Oracle::aggregatePrice(env, "XRP", "USD", {{{owner, std::nullopt}}});
             BEAST_EXPECT(ret[jss::error].asString() == "oracleMalformed");
+            BEAST_EXPECT(ret[jss::error_code] == RpcOracleMalformed);
+            BEAST_EXPECT(ret[jss::error_message].asString() == "Oracle request is malformed.");
 
             // invalid owner
             ret = Oracle::aggregatePrice(env, "XRP", "USD", {{{some, 1}}});
             BEAST_EXPECT(ret[jss::error].asString() == "objectNotFound");
+            BEAST_EXPECT(ret[jss::error_code] == RpcObjectNotFound);
+            BEAST_EXPECT(
+                ret[jss::error_message].asString() == "The requested object was not found.");
             // missing account
             ret = Oracle::aggregatePrice(env, "XRP", "USD", {{{std::nullopt, 1}}});
             BEAST_EXPECT(ret[jss::error].asString() == "oracleMalformed");
+            BEAST_EXPECT(ret[jss::error_code] == RpcOracleMalformed);
+            BEAST_EXPECT(ret[jss::error_message].asString() == "Oracle request is malformed.");
 
             // oracles have wrong asset pair
             env.fund(XRP(1'000), owner);
@@ -122,6 +152,9 @@ public:
                 });
             ret = Oracle::aggregatePrice(env, "XRP", "USD", {{{owner, oracle.documentID()}}});
             BEAST_EXPECT(ret[jss::error].asString() == "objectNotFound");
+            BEAST_EXPECT(ret[jss::error_code] == RpcObjectNotFound);
+            BEAST_EXPECT(
+                ret[jss::error_message].asString() == "The requested object was not found.");
 
             // invalid trim value
             std::vector<AnyValue> const invalidTrim = {kNoneTag, 0, 26, -1, 1.2, "", "none", "1.2"};
@@ -130,6 +163,8 @@ public:
                 ret =
                     Oracle::aggregatePrice(env, "XRP", "USD", {{{owner, oracle.documentID()}}}, v);
                 BEAST_EXPECT(ret[jss::error].asString() == "invalidParams");
+                BEAST_EXPECT(ret[jss::error_code] == RpcInvalidParams);
+                BEAST_EXPECT(ret[jss::error_message].asString() == "Invalid parameters.");
             }
 
             // invalid time threshold value
@@ -139,6 +174,8 @@ public:
                 ret = Oracle::aggregatePrice(
                     env, "XRP", "USD", {{{owner, oracle.documentID()}}}, std::nullopt, v);
                 BEAST_EXPECT(ret[jss::error].asString() == "invalidParams");
+                BEAST_EXPECT(ret[jss::error_code] == RpcInvalidParams);
+                BEAST_EXPECT(ret[jss::error_message].asString() == "Invalid parameters.");
             }
         }
 
@@ -157,6 +194,8 @@ public:
             }
             auto const ret = Oracle::aggregatePrice(env, "XRP", "USD", oracles);
             BEAST_EXPECT(ret[jss::error].asString() == "oracleMalformed");
+            BEAST_EXPECT(ret[jss::error_code] == RpcOracleMalformed);
+            BEAST_EXPECT(ret[jss::error_message].asString() == "Oracle request is malformed.");
         }
     }
 
@@ -457,6 +496,8 @@ public:
         // a nullptr dereference.
         auto const ret = Oracle::aggregatePrice(env, "XRP", "USD", oracles);
         BEAST_EXPECT(ret[jss::error].asString() == "objectNotFound");
+        BEAST_EXPECT(ret[jss::error_code] == RpcObjectNotFound);
+        BEAST_EXPECT(ret[jss::error_message].asString() == "The requested object was not found.");
     }
 
     void

src/test/rpc/KeyGeneration_test.cpp

@@ -209,7 +209,12 @@ public:
         params[jss::seed_hex] = strings.masterSeedHex;
 
         // Secret fields are mutually exclusive.
-        BEAST_EXPECT(containsError(walletPropose(params)));
+        auto const result = walletPropose(params);
+        BEAST_EXPECT(result[jss::error] == "invalidParams");
+        BEAST_EXPECT(result[jss::error_code] == RpcInvalidParams);
+        BEAST_EXPECT(
+            result[jss::error_message] ==
+            "Exactly one of the following must be specified: passphrase, seed or seed_hex");
     }
 
     void
@@ -223,7 +228,8 @@ public:
             params[jss::key_type] = "secp256k1";
             params[jss::passphrase] = 20160506;
             auto result = walletPropose(params);
-            BEAST_EXPECT(containsError(result));
+            BEAST_EXPECT(result[jss::error] == "invalidParams");
+            BEAST_EXPECT(result[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(result[jss::error_message] == "Invalid field 'passphrase', not string.");
         }
 
@@ -232,7 +238,8 @@ public:
             params[jss::key_type] = "secp256k1";
             params[jss::seed] = json::ValueType::Object;
             auto result = walletPropose(params);
-            BEAST_EXPECT(containsError(result));
+            BEAST_EXPECT(result[jss::error] == "invalidParams");
+            BEAST_EXPECT(result[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(result[jss::error_message] == "Invalid field 'seed', not string.");
         }
 
@@ -241,7 +248,8 @@ public:
             params[jss::key_type] = "ed25519";
             params[jss::seed_hex] = json::ValueType::Array;
             auto result = walletPropose(params);
-            BEAST_EXPECT(containsError(result));
+            BEAST_EXPECT(result[jss::error] == "invalidParams");
+            BEAST_EXPECT(result[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(result[jss::error_message] == "Invalid field 'seed_hex', not string.");
         }
 
@@ -253,7 +261,8 @@ public:
             params[jss::seed_hex] = common::gMasterSeedHex;
             params[jss::seed] = common::gMasterSeed;
             auto result = walletPropose(params);
-            BEAST_EXPECT(containsError(result));
+            BEAST_EXPECT(result[jss::error] == "invalidParams");
+            BEAST_EXPECT(result[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(
                 result[jss::error_message] ==
                 "Exactly one of the following must be specified: passphrase, "
@@ -266,7 +275,8 @@ public:
             params[jss::key_type] = "prime256v1";
             params[jss::passphrase] = common::gMasterKey;
             auto result = walletPropose(params);
-            BEAST_EXPECT(containsError(result));
+            BEAST_EXPECT(result[jss::error] == "invalidParams");
+            BEAST_EXPECT(result[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(result[jss::error_message] == "Invalid parameters.");
         }
 
@@ -275,7 +285,8 @@ public:
             params[jss::key_type] = json::ValueType::Object;
             params[jss::seed_hex] = common::gMasterSeedHex;
             auto result = walletPropose(params);
-            BEAST_EXPECT(containsError(result));
+            BEAST_EXPECT(result[jss::error] == "invalidParams");
+            BEAST_EXPECT(result[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(result[jss::error_message] == "Invalid field 'key_type', not string.");
         }
 
@@ -284,7 +295,8 @@ public:
             params[jss::key_type] = json::ValueType::Array;
             params[jss::seed] = common::gMasterSeed;
             auto result = walletPropose(params);
-            BEAST_EXPECT(containsError(result));
+            BEAST_EXPECT(result[jss::error] == "invalidParams");
+            BEAST_EXPECT(result[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(result[jss::error_message] == "Invalid field 'key_type', not string.");
         }
     }
@@ -402,8 +414,9 @@ public:
             json::Value error;
             params[jss::secret] = 314159265;
             auto const ret = keypairForSignature(params, error);
-            BEAST_EXPECT(containsError(error));
             BEAST_EXPECT(!ret);
+            BEAST_EXPECT(error[jss::error] == "invalidParams");
+            BEAST_EXPECT(error[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(error[jss::error_message] == "Invalid field 'secret', not string.");
         }
 
@@ -414,8 +427,9 @@ public:
             params[jss::secret].append("array:0");
 
             auto const ret = keypairForSignature(params, error);
-            BEAST_EXPECT(containsError(error));
             BEAST_EXPECT(!ret);
+            BEAST_EXPECT(error[jss::error] == "invalidParams");
+            BEAST_EXPECT(error[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(error[jss::error_message] == "Invalid field 'secret', not string.");
         }
 
@@ -427,8 +441,9 @@ public:
             params[jss::secret]["number"] = 702;
 
             auto const ret = keypairForSignature(params, error);
-            BEAST_EXPECT(containsError(error));
             BEAST_EXPECT(!ret);
+            BEAST_EXPECT(error[jss::error] == "invalidParams");
+            BEAST_EXPECT(error[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(error[jss::error_message] == "Invalid field 'secret', not string.");
         }
 
@@ -440,8 +455,9 @@ public:
             params[jss::secret] = common::gMasterSeed;
 
             auto const ret = keypairForSignature(params, error);
-            BEAST_EXPECT(containsError(error));
             BEAST_EXPECT(!ret);
+            BEAST_EXPECT(error[jss::error] == "invalidParams");
+            BEAST_EXPECT(error[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(
                 error[jss::error_message] ==
                 "The secret field is not allowed if key_type is used.");
@@ -455,8 +471,9 @@ public:
             params[jss::passphrase] = common::gMasterKey;
 
             auto const ret = keypairForSignature(params, error);
-            BEAST_EXPECT(containsError(error));
             BEAST_EXPECT(!ret);
+            BEAST_EXPECT(error[jss::error] == "invalidParams");
+            BEAST_EXPECT(error[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(error[jss::error_message] == "Invalid field 'key_type'.");
         }
 
@@ -467,8 +484,9 @@ public:
             params[jss::seed_hex] = common::gMasterSeedHex;
 
             auto const ret = keypairForSignature(params, error);
-            BEAST_EXPECT(containsError(error));
             BEAST_EXPECT(!ret);
+            BEAST_EXPECT(error[jss::error] == "invalidParams");
+            BEAST_EXPECT(error[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(error[jss::error_message] == "Invalid field 'key_type', not string.");
         }
 
@@ -479,8 +497,9 @@ public:
             params[jss::seed] = common::gMasterSeed;
 
             auto const ret = keypairForSignature(params, error);
-            BEAST_EXPECT(containsError(error));
             BEAST_EXPECT(!ret);
+            BEAST_EXPECT(error[jss::error] == "invalidParams");
+            BEAST_EXPECT(error[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(error[jss::error_message] == "Invalid field 'key_type', not string.");
         }
 
@@ -492,8 +511,9 @@ public:
             params[jss::passphrase] = 1234567890;
 
             auto const ret = keypairForSignature(params, error);
-            BEAST_EXPECT(containsError(error));
             BEAST_EXPECT(!ret);
+            BEAST_EXPECT(error[jss::error] == "invalidParams");
+            BEAST_EXPECT(error[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(error[jss::error_message] == "Invalid field 'passphrase', not string.");
         }
 
@@ -504,8 +524,9 @@ public:
             params[jss::passphrase] = json::ValueType::Object;
 
             auto const ret = keypairForSignature(params, error);
-            BEAST_EXPECT(containsError(error));
             BEAST_EXPECT(!ret);
+            BEAST_EXPECT(error[jss::error] == "invalidParams");
+            BEAST_EXPECT(error[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(error[jss::error_message] == "Invalid field 'passphrase', not string.");
         }
 
@@ -516,8 +537,9 @@ public:
             params[jss::passphrase] = json::ValueType::Array;
 
             auto const ret = keypairForSignature(params, error);
-            BEAST_EXPECT(containsError(error));
             BEAST_EXPECT(!ret);
+            BEAST_EXPECT(error[jss::error] == "invalidParams");
+            BEAST_EXPECT(error[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(error[jss::error_message] == "Invalid field 'passphrase', not string.");
         }
 
@@ -528,8 +550,9 @@ public:
             params[jss::passphrase] = "";
 
             auto const ret = keypairForSignature(params, error);
-            BEAST_EXPECT(containsError(error));
             BEAST_EXPECT(!ret);
+            BEAST_EXPECT(error[jss::error] == "badSeed");
+            BEAST_EXPECT(error[jss::error_code] == RpcBadSeed);
             BEAST_EXPECT(error[jss::error_message] == "Disallowed seed.");
         }
 
@@ -541,8 +564,9 @@ public:
             params[jss::seed] = 443556;
 
             auto const ret = keypairForSignature(params, error);
-            BEAST_EXPECT(containsError(error));
             BEAST_EXPECT(!ret);
+            BEAST_EXPECT(error[jss::error] == "invalidParams");
+            BEAST_EXPECT(error[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(error[jss::error_message] == "Invalid field 'seed', not string.");
         }
 
@@ -553,8 +577,9 @@ public:
             params[jss::seed] = json::ValueType::Object;
 
             auto const ret = keypairForSignature(params, error);
-            BEAST_EXPECT(containsError(error));
             BEAST_EXPECT(!ret);
+            BEAST_EXPECT(error[jss::error] == "invalidParams");
+            BEAST_EXPECT(error[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(error[jss::error_message] == "Invalid field 'seed', not string.");
         }
 
@@ -565,8 +590,9 @@ public:
             params[jss::seed] = json::ValueType::Array;
 
             auto const ret = keypairForSignature(params, error);
-            BEAST_EXPECT(containsError(error));
             BEAST_EXPECT(!ret);
+            BEAST_EXPECT(error[jss::error] == "invalidParams");
+            BEAST_EXPECT(error[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(error[jss::error_message] == "Invalid field 'seed', not string.");
         }
 
@@ -577,8 +603,9 @@ public:
             params[jss::seed] = "";
 
             auto const ret = keypairForSignature(params, error);
-            BEAST_EXPECT(containsError(error));
             BEAST_EXPECT(!ret);
+            BEAST_EXPECT(error[jss::error] == "badSeed");
+            BEAST_EXPECT(error[jss::error_code] == RpcBadSeed);
             BEAST_EXPECT(error[jss::error_message] == "Disallowed seed.");
         }
 
@@ -589,8 +616,9 @@ public:
             params[jss::seed] = "s M V s h z D F p t Z E m h s";
 
             auto const ret = keypairForSignature(params, error);
-            BEAST_EXPECT(containsError(error));
             BEAST_EXPECT(!ret);
+            BEAST_EXPECT(error[jss::error] == "badSeed");
+            BEAST_EXPECT(error[jss::error_code] == RpcBadSeed);
             BEAST_EXPECT(error[jss::error_message] == "Disallowed seed.");
         }
 
@@ -601,8 +629,9 @@ public:
             params[jss::seed] = "pnnjkbnobnml43679nbvjdsklnbjs";
 
             auto const ret = keypairForSignature(params, error);
-            BEAST_EXPECT(containsError(error));
             BEAST_EXPECT(!ret);
+            BEAST_EXPECT(error[jss::error] == "badSeed");
+            BEAST_EXPECT(error[jss::error_code] == RpcBadSeed);
             BEAST_EXPECT(error[jss::error_message] == "Disallowed seed.");
         }
 
@@ -614,8 +643,9 @@ public:
             params[jss::seed_hex] = 443556;
 
             auto const ret = keypairForSignature(params, error);
-            BEAST_EXPECT(containsError(error));
             BEAST_EXPECT(!ret);
+            BEAST_EXPECT(error[jss::error] == "invalidParams");
+            BEAST_EXPECT(error[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(error[jss::error_message] == "Invalid field 'seed_hex', not string.");
         }
 
@@ -626,8 +656,9 @@ public:
             params[jss::seed_hex] = json::ValueType::Object;
 
             auto const ret = keypairForSignature(params, error);
-            BEAST_EXPECT(containsError(error));
             BEAST_EXPECT(!ret);
+            BEAST_EXPECT(error[jss::error] == "invalidParams");
+            BEAST_EXPECT(error[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(error[jss::error_message] == "Invalid field 'seed_hex', not string.");
         }
 
@@ -638,8 +669,9 @@ public:
             params[jss::seed_hex] = json::ValueType::Array;
 
             auto const ret = keypairForSignature(params, error);
-            BEAST_EXPECT(containsError(error));
             BEAST_EXPECT(!ret);
+            BEAST_EXPECT(error[jss::error] == "invalidParams");
+            BEAST_EXPECT(error[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(error[jss::error_message] == "Invalid field 'seed_hex', not string.");
         }
 
@@ -650,8 +682,9 @@ public:
             params[jss::seed_hex] = "";
 
             auto const ret = keypairForSignature(params, error);
-            BEAST_EXPECT(containsError(error));
             BEAST_EXPECT(!ret);
+            BEAST_EXPECT(error[jss::error] == "badSeed");
+            BEAST_EXPECT(error[jss::error_code] == RpcBadSeed);
             BEAST_EXPECT(error[jss::error_message] == "Disallowed seed.");
         }
 
@@ -662,8 +695,9 @@ public:
             params[jss::seed_hex] = "A670A19B";
 
             auto const ret = keypairForSignature(params, error);
-            BEAST_EXPECT(containsError(error));
             BEAST_EXPECT(!ret);
+            BEAST_EXPECT(error[jss::error] == "badSeed");
+            BEAST_EXPECT(error[jss::error_code] == RpcBadSeed);
             BEAST_EXPECT(error[jss::error_message] == "Disallowed seed.");
         }
 
@@ -674,8 +708,9 @@ public:
             params[jss::seed_hex] = common::gPassphrase;
 
             auto const ret = keypairForSignature(params, error);
-            BEAST_EXPECT(containsError(error));
             BEAST_EXPECT(!ret);
+            BEAST_EXPECT(error[jss::error] == "badSeed");
+            BEAST_EXPECT(error[jss::error_code] == RpcBadSeed);
             BEAST_EXPECT(error[jss::error_message] == "Disallowed seed.");
         }
 
@@ -686,8 +721,9 @@ public:
             params[jss::seed_hex] = "BE6A670A19B209E112146D0A7ED2AAD72567D0FC913";
 
             auto const ret = keypairForSignature(params, error);
-            BEAST_EXPECT(containsError(error));
             BEAST_EXPECT(!ret);
+            BEAST_EXPECT(error[jss::error] == "badSeed");
+            BEAST_EXPECT(error[jss::error_code] == RpcBadSeed);
             BEAST_EXPECT(error[jss::error_message] == "Disallowed seed.");
         }
     }
@@ -723,7 +759,8 @@ public:
 
                 auto const ret = keypairForSignature(params, error);
 
-                BEAST_EXPECT(containsError(error));
+                BEAST_EXPECT(error[jss::error] == "badSeed");
+                BEAST_EXPECT(error[jss::error_code] == RpcBadSeed);
                 BEAST_EXPECT(
                     error[jss::error_message] == "Specified seed is for an Ed25519 wallet.");
             }
@@ -754,7 +791,8 @@ public:
 
                 auto const ret = keypairForSignature(params, error);
 
-                BEAST_EXPECT(containsError(error));
+                BEAST_EXPECT(error[jss::error] == "badSeed");
+                BEAST_EXPECT(error[jss::error_code] == RpcBadSeed);
                 BEAST_EXPECT(
                     error[jss::error_message] == "Specified seed is for an Ed25519 wallet.");
             }

src/test/rpc/LedgerData_test.cpp

@@ -17,6 +17,7 @@
 #include <xrpl/json/json_value.h>
 #include <xrpl/json/to_string.h>
 #include <xrpl/ledger/View.h>
+#include <xrpl/protocol/ErrorCodes.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/SField.h>
 #include <xrpl/protocol/Serializer.h>
@@ -131,8 +132,9 @@ public:
             json::Value jvParams;
             jvParams[jss::limit] = "0";  // NOT an integer
             auto const jrr = env.rpc("json", "ledger_data", to_string(jvParams))[jss::result];
-            BEAST_EXPECT(jrr[jss::error] == "invalidParams");
             BEAST_EXPECT(jrr[jss::status] == "error");
+            BEAST_EXPECT(jrr[jss::error] == "invalidParams");
+            BEAST_EXPECT(jrr[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(jrr[jss::error_message] == "Invalid field 'limit', not integer.");
         }
 
@@ -141,8 +143,9 @@ public:
             json::Value jvParams;
             jvParams[jss::marker] = "NOT_A_MARKER";
             auto const jrr = env.rpc("json", "ledger_data", to_string(jvParams))[jss::result];
-            BEAST_EXPECT(jrr[jss::error] == "invalidParams");
             BEAST_EXPECT(jrr[jss::status] == "error");
+            BEAST_EXPECT(jrr[jss::error] == "invalidParams");
+            BEAST_EXPECT(jrr[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(jrr[jss::error_message] == "Invalid field 'marker', not valid.");
         }
 
@@ -151,8 +154,9 @@ public:
             json::Value jvParams;
             jvParams[jss::marker] = 1;
             auto const jrr = env.rpc("json", "ledger_data", to_string(jvParams))[jss::result];
-            BEAST_EXPECT(jrr[jss::error] == "invalidParams");
             BEAST_EXPECT(jrr[jss::status] == "error");
+            BEAST_EXPECT(jrr[jss::error] == "invalidParams");
+            BEAST_EXPECT(jrr[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(jrr[jss::error_message] == "Invalid field 'marker', not valid.");
         }
 
@@ -161,8 +165,9 @@ public:
             json::Value jvParams;
             jvParams[jss::ledger_index] = 10u;
             auto const jrr = env.rpc("json", "ledger_data", to_string(jvParams))[jss::result];
-            BEAST_EXPECT(jrr[jss::error] == "lgrNotFound");
             BEAST_EXPECT(jrr[jss::status] == "error");
+            BEAST_EXPECT(jrr[jss::error] == "lgrNotFound");
+            BEAST_EXPECT(jrr[jss::error_code] == RpcLgrNotFound);
             BEAST_EXPECT(jrr[jss::error_message] == "ledgerNotFound");
         }
 
@@ -171,8 +176,9 @@ public:
             json::Value jvParams;
             jvParams[jss::binary] = "true";
             auto const jrr = env.rpc("json", "ledger_data", to_string(jvParams))[jss::result];
-            BEAST_EXPECT(jrr[jss::error] == "invalidParams");
             BEAST_EXPECT(jrr[jss::status] == "error");
+            BEAST_EXPECT(jrr[jss::error] == "invalidParams");
+            BEAST_EXPECT(jrr[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(jrr[jss::error_message] == "Invalid field 'binary', not boolean.");
         }
     }
@@ -459,8 +465,8 @@ public:
                 jvParams[jss::ledger_index] = "current";
                 jvParams[jss::type] = "misspelling";
                 auto const jrr = env.rpc("json", "ledger_data", to_string(jvParams))[jss::result];
-                BEAST_EXPECT(jrr.isMember("error"));
                 BEAST_EXPECT(jrr["error"] == "invalidParams");
+                BEAST_EXPECT(jrr["error_code"] == RpcInvalidParams);
                 BEAST_EXPECT(jrr["error_message"] == "Invalid field 'type'.");
             }
         }

src/test/rpc/LedgerEntry_test.cpp

@@ -153,6 +153,7 @@ class LedgerEntry_test : public beast::unit_test::Suite
     checkErrorValue(
         json::Value const& jv,
         std::string const& err,
+        ErrorCodeI code,
         std::string const& msg,
         std::source_location const location = std::source_location::current())
     {
@@ -165,6 +166,14 @@ class LedgerEntry_test : public beast::unit_test::Suite
                 "Expected error " + err + ", received " + jv[jss::error].asString() + ", at line " +
                     std::to_string(location.line()) + ", " + jv.toStyledString());
         }
+        if (BEAST_EXPECT(jv.isMember(jss::error_code)))
+        {
+            BEAST_EXPECTS(
+                jv[jss::error_code] == code,
+                "Expected error code " + std::to_string(code) + ", received " +
+                    jv[jss::error_code].asString() + ", at line " +
+                    std::to_string(location.line()) + ", " + jv.toStyledString());
+        }
         if (msg.empty())
         {
             BEAST_EXPECTS(
@@ -340,12 +349,21 @@ class LedgerEntry_test : public beast::unit_test::Suite
                     apiVersion, "json", "ledger_entry", to_string(correctRequest))[jss::result];
                 if (apiVersion < 2u)
                 {
-                    checkErrorValue(jrr, "unknownOption", "", location);
+                    BEAST_EXPECTS(jrr[jss::status] == "error", std::to_string(location.line()));
+                    BEAST_EXPECTS(
+                        jrr[jss::error] == "unknownOption", std::to_string(location.line()));
+                    BEAST_EXPECTS(!jrr.isMember(jss::error_code), std::to_string(location.line()));
+                    BEAST_EXPECTS(
+                        jrr[jss::error_message].isNull(), std::to_string(location.line()));
                 }
                 else
                 {
                     checkErrorValue(
-                        jrr, "invalidParams", "No ledger_entry params provided.", location);
+                        jrr,
+                        "invalidParams",
+                        RpcInvalidParams,
+                        "No ledger_entry params provided.",
+                        location);
                 }
             }
             auto const tryField = [&](json::Value fieldValue) -> void {
@@ -354,7 +372,7 @@ class LedgerEntry_test : public beast::unit_test::Suite
                     apiVersion, "json", "ledger_entry", to_string(correctRequest))[jss::result];
                 auto const expectedErrMsg = rpc::expectedFieldMessage(
                     fieldName, typeNameOverride.value_or(getTypeName(typeID)));
-                checkErrorValue(jrr, expectedError, expectedErrMsg, location);
+                checkErrorValue(jrr, expectedError, RpcInvalidParams, expectedErrMsg, location);
             };
 
             auto const& badValues = getBadValues(typeID);
@@ -387,13 +405,21 @@ class LedgerEntry_test : public beast::unit_test::Suite
                 json::Value const jrr = env.rpc(
                     apiVersion, "json", "ledger_entry", to_string(correctRequest))[jss::result];
                 checkErrorValue(
-                    jrr, "malformedRequest", rpc::missingFieldMessage(fieldName.cStr()), location);
+                    jrr,
+                    "malformedRequest",
+                    RpcInvalidParams,
+                    rpc::missingFieldMessage(fieldName.cStr()),
+                    location);
 
                 correctRequest[parentFieldName][fieldName] = json::ValueType::Null;
                 json::Value const jrr2 = env.rpc(
                     apiVersion, "json", "ledger_entry", to_string(correctRequest))[jss::result];
                 checkErrorValue(
-                    jrr2, "malformedRequest", rpc::missingFieldMessage(fieldName.cStr()), location);
+                    jrr2,
+                    "malformedRequest",
+                    RpcInvalidParams,
+                    rpc::missingFieldMessage(fieldName.cStr()),
+                    location);
             }
             auto const tryField = [&](json::Value fieldValue) -> void {
                 correctRequest[parentFieldName][fieldName] = fieldValue;
@@ -403,6 +429,7 @@ class LedgerEntry_test : public beast::unit_test::Suite
                 checkErrorValue(
                     jrr,
                     expectedError,
+                    RpcInvalidParams,
                     rpc::expectedFieldMessage(fieldName, getTypeName(typeID)),
                     location);
             };
@@ -497,7 +524,7 @@ class LedgerEntry_test : public beast::unit_test::Suite
                 "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
                 "AA";
             auto const jrr = env.rpc("json", "ledger_entry", to_string(jvParams))[jss::result];
-            checkErrorValue(jrr, "lgrNotFound", "ledgerNotFound");
+            checkErrorValue(jrr, "lgrNotFound", RpcLgrNotFound, "ledgerNotFound");
         }
         {
             // Missing ledger_entry ledger_hash
@@ -511,7 +538,10 @@ class LedgerEntry_test : public beast::unit_test::Suite
                     json::Value const jrr = env.rpc(
                         apiVersion, "json", "ledger_entry", to_string(jvParams))[jss::result];
                     checkErrorValue(
-                        jrr, "invalidParams", "Invalid field 'ledger_hash', not hex string.");
+                        jrr,
+                        "invalidParams",
+                        RpcInvalidParams,
+                        "Invalid field 'ledger_hash', not hex string.");
                 };
 
                 auto const& badValues = getBadValues(typeId);
@@ -530,7 +560,7 @@ class LedgerEntry_test : public beast::unit_test::Suite
                 "00000000000000000000000000000000000000000000000000000000000000"
                 "00";
             auto const jrr = env.rpc("json", "ledger_entry", to_string(jvParams))[jss::result];
-            checkErrorValue(jrr, "entryNotFound", "Entry not found.");
+            checkErrorValue(jrr, "entryNotFound", RpcEntryNotFound, "Entry not found.");
         }
 
         forAllApiVersions([&, this](unsigned apiVersion) {
@@ -546,11 +576,15 @@ class LedgerEntry_test : public beast::unit_test::Suite
 
                 if (apiVersion < 2u)
                 {
-                    checkErrorValue(jrr, "unknownOption", "");
+                    BEAST_EXPECT(jrr[jss::status] == "error");
+                    BEAST_EXPECT(jrr[jss::error] == "unknownOption");
+                    BEAST_EXPECT(!jrr.isMember(jss::error_code));
+                    BEAST_EXPECT(jrr[jss::error_message].isNull());
                 }
                 else
                 {
-                    checkErrorValue(jrr, "invalidParams", "No ledger_entry params provided.");
+                    checkErrorValue(
+                        jrr, "invalidParams", RpcInvalidParams, "No ledger_entry params provided.");
                 }
             }
         });
@@ -655,7 +689,7 @@ class LedgerEntry_test : public beast::unit_test::Suite
             jvParams[jss::ledger_hash] = ledgerHash;
             json::Value const jrr =
                 env.rpc("json", "ledger_entry", to_string(jvParams))[jss::result];
-            checkErrorValue(jrr, "entryNotFound", "Entry not found.");
+            checkErrorValue(jrr, "entryNotFound", RpcEntryNotFound, "Entry not found.");
         }
     }
 
@@ -854,7 +888,7 @@ class LedgerEntry_test : public beast::unit_test::Suite
             jvParams[jss::ledger_hash] = ledgerHash;
             json::Value const jrr =
                 env.rpc("json", "ledger_entry", to_string(jvParams))[jss::result];
-            checkErrorValue(jrr, "entryNotFound", "Entry not found.");
+            checkErrorValue(jrr, "entryNotFound", RpcEntryNotFound, "Entry not found.");
         }
         {
             // Request an index that is not a check.  We'll use alice's
@@ -872,7 +906,8 @@ class LedgerEntry_test : public beast::unit_test::Suite
             jvParams[jss::ledger_hash] = ledgerHash;
             json::Value const jrr =
                 env.rpc("json", "ledger_entry", to_string(jvParams))[jss::result];
-            checkErrorValue(jrr, "unexpectedLedgerType", "Unexpected ledger type.");
+            checkErrorValue(
+                jrr, "unexpectedLedgerType", RpcUnexpectedLedgerType, "Unexpected ledger type.");
         }
         {
             // Check malformed cases
@@ -931,7 +966,7 @@ class LedgerEntry_test : public beast::unit_test::Suite
                 env,
                 "48004829F915654A81B11C4AB8218D96FED67F209B58328A72314FB6EA288B"
                 "E4");
-            checkErrorValue(jv[jss::result], "entryNotFound", "Entry not found.");
+            checkErrorValue(jv[jss::result], "entryNotFound", RpcEntryNotFound, "Entry not found.");
         }
 
         {
@@ -1126,7 +1161,8 @@ class LedgerEntry_test : public beast::unit_test::Suite
                 auto const expectedErrMsg = fieldValue.isNull()
                     ? rpc::missingFieldMessage(jss::issuer.cStr())
                     : rpc::expectedFieldMessage(jss::issuer, "AccountID");
-                checkErrorValue(jrr, "malformedAuthorizedCredentials", expectedErrMsg);
+                checkErrorValue(
+                    jrr, "malformedAuthorizedCredentials", RpcInvalidParams, expectedErrMsg);
             };
 
             auto const& badValues = getBadValues(FieldType::AccountField);
@@ -1155,6 +1191,7 @@ class LedgerEntry_test : public beast::unit_test::Suite
             checkErrorValue(
                 jrr[jss::result],
                 "malformedAuthorizedCredentials",
+                RpcInvalidParams,
                 rpc::expectedFieldMessage(jss::authorized_credentials, "array"));
         }
 
@@ -1177,7 +1214,8 @@ class LedgerEntry_test : public beast::unit_test::Suite
                 auto const expectedErrMsg = fieldValue.isNull()
                     ? rpc::missingFieldMessage(jss::credential_type.cStr())
                     : rpc::expectedFieldMessage(jss::credential_type, "hex string");
-                checkErrorValue(jrr, "malformedAuthorizedCredentials", expectedErrMsg);
+                checkErrorValue(
+                    jrr, "malformedAuthorizedCredentials", RpcInvalidParams, expectedErrMsg);
             };
 
             auto const& badValues = getBadValues(FieldType::BlobField);
@@ -1207,6 +1245,7 @@ class LedgerEntry_test : public beast::unit_test::Suite
             checkErrorValue(
                 jrr[jss::result],
                 "malformedRequest",
+                RpcInvalidParams,
                 "Must have exactly one of `authorized` and "
                 "`authorized_credentials`.");
         }
@@ -1239,6 +1278,7 @@ class LedgerEntry_test : public beast::unit_test::Suite
             checkErrorValue(
                 jrr[jss::result],
                 "malformedAuthorizedCredentials",
+                RpcInvalidParams,
                 "Invalid field 'authorized_credentials', not array of objects.");
         }
 
@@ -1257,6 +1297,7 @@ class LedgerEntry_test : public beast::unit_test::Suite
             checkErrorValue(
                 jrr[jss::result],
                 "malformedAuthorizedCredentials",
+                RpcInvalidParams,
                 "Invalid field 'authorized_credentials', not array of objects.");
         }
 
@@ -1271,6 +1312,7 @@ class LedgerEntry_test : public beast::unit_test::Suite
             checkErrorValue(
                 jrr[jss::result],
                 "malformedAuthorizedCredentials",
+                RpcInvalidParams,
                 "Invalid field 'authorized_credentials', array empty.");
         }
 
@@ -1308,6 +1350,7 @@ class LedgerEntry_test : public beast::unit_test::Suite
             checkErrorValue(
                 jrr[jss::result],
                 "malformedAuthorizedCredentials",
+                RpcInvalidParams,
                 "Invalid field 'authorized_credentials', array too long.");
         }
     }
@@ -1443,7 +1486,10 @@ class LedgerEntry_test : public beast::unit_test::Suite
             json::Value const jrr =
                 env.rpc("json", "ledger_entry", to_string(jvParams))[jss::result];
             checkErrorValue(
-                jrr, "malformedRequest", "Must have exactly one of `owner` and `dir_root` fields.");
+                jrr,
+                "malformedRequest",
+                RpcInvalidParams,
+                "Must have exactly one of `owner` and `dir_root` fields.");
         }
         {
             // Incomplete directory object.  Missing both dir_root and owner.
@@ -1454,7 +1500,10 @@ class LedgerEntry_test : public beast::unit_test::Suite
             json::Value const jrr =
                 env.rpc("json", "ledger_entry", to_string(jvParams))[jss::result];
             checkErrorValue(
-                jrr, "malformedRequest", "Must have exactly one of `owner` and `dir_root` fields.");
+                jrr,
+                "malformedRequest",
+                RpcInvalidParams,
+                "Must have exactly one of `owner` and `dir_root` fields.");
         }
     }
 
@@ -1617,7 +1666,7 @@ class LedgerEntry_test : public beast::unit_test::Suite
             jvParams[jss::nft_offer][jss::seq] = offerSeq + 1000;
             json::Value const jrr =
                 env.rpc("json", "ledger_entry", to_string(jvParams))[jss::result];
-            checkErrorValue(jrr, "entryNotFound", "Entry not found.");
+            checkErrorValue(jrr, "entryNotFound", RpcEntryNotFound, "Entry not found.");
         }
 
         // negative tests
@@ -1835,7 +1884,7 @@ class LedgerEntry_test : public beast::unit_test::Suite
             jvParams[jss::ledger_hash] = ledgerHash;
             json::Value const jrr =
                 env.rpc("json", "ledger_entry", to_string(jvParams))[jss::result];
-            checkErrorValue(jrr, "entryNotFound", "Entry not found.");
+            checkErrorValue(jrr, "entryNotFound", RpcEntryNotFound, "Entry not found.");
         }
         {
             // Request an index that is not a payment channel.
@@ -1844,7 +1893,7 @@ class LedgerEntry_test : public beast::unit_test::Suite
             jvParams[jss::ledger_hash] = ledgerHash;
             json::Value const jrr =
                 env.rpc("json", "ledger_entry", to_string(jvParams))[jss::result];
-            checkErrorValue(jrr, "entryNotFound", "Entry not found.");
+            checkErrorValue(jrr, "entryNotFound", RpcEntryNotFound, "Entry not found.");
         }
 
         {
@@ -1919,6 +1968,7 @@ class LedgerEntry_test : public beast::unit_test::Suite
                 checkErrorValue(
                     jrr,
                     "malformedRequest",
+                    RpcInvalidParams,
                     "Invalid field 'accounts', not length-2 array of "
                     "Accounts.");
             }
@@ -1937,6 +1987,7 @@ class LedgerEntry_test : public beast::unit_test::Suite
                 checkErrorValue(
                     jrr,
                     "malformedRequest",
+                    RpcInvalidParams,
                     "Invalid field 'accounts', not length-2 array of "
                     "Accounts.");
             }
@@ -1957,6 +2008,7 @@ class LedgerEntry_test : public beast::unit_test::Suite
                         checkErrorValue(
                             jrr,
                             "malformedAddress",
+                            RpcInvalidParams,
                             rpc::expectedFieldMessage(jss::accounts, "array of Accounts"));
                     }
 
@@ -1972,6 +2024,7 @@ class LedgerEntry_test : public beast::unit_test::Suite
                         checkErrorValue(
                             jrr,
                             "malformedAddress",
+                            RpcInvalidParams,
                             rpc::expectedFieldMessage(jss::accounts, "array of Accounts"));
                     }
                 };
@@ -1994,7 +2047,8 @@ class LedgerEntry_test : public beast::unit_test::Suite
                 jvParams[jss::ledger_hash] = ledgerHash;
                 json::Value const jrr =
                     env.rpc("json", "ledger_entry", to_string(jvParams))[jss::result];
-                checkErrorValue(jrr, "malformedRequest", "Cannot have a trustline to self.");
+                checkErrorValue(
+                    jrr, "malformedRequest", RpcInvalidParams, "Cannot have a trustline to self.");
             }
         }
     }
@@ -2048,7 +2102,7 @@ class LedgerEntry_test : public beast::unit_test::Suite
             jvParams[jss::ledger_hash] = ledgerHash;
             json::Value const jrr =
                 env.rpc("json", "ledger_entry", to_string(jvParams))[jss::result];
-            checkErrorValue(jrr, "entryNotFound", "Entry not found.");
+            checkErrorValue(jrr, "entryNotFound", RpcEntryNotFound, "Entry not found.");
         }
         {
             // Request an index that is not a signer list.
@@ -2057,7 +2111,7 @@ class LedgerEntry_test : public beast::unit_test::Suite
             jvParams[jss::ledger_hash] = ledgerHash;
             json::Value const jrr =
                 env.rpc("json", "ledger_entry", to_string(jvParams))[jss::result];
-            checkErrorValue(jrr, "entryNotFound", "Entry not found.");
+            checkErrorValue(jrr, "entryNotFound", RpcEntryNotFound, "Entry not found.");
         }
 
         {
@@ -2148,7 +2202,7 @@ class LedgerEntry_test : public beast::unit_test::Suite
             jvParams[jss::ledger_hash] = ledgerHash;
             json::Value const jrr =
                 env.rpc("json", "ledger_entry", to_string(jvParams))[jss::result];
-            checkErrorValue(jrr, "entryNotFound", "Entry not found.");
+            checkErrorValue(jrr, "entryNotFound", RpcEntryNotFound, "Entry not found.");
         }
         {
             // First real ticket requested by index.
@@ -2184,7 +2238,7 @@ class LedgerEntry_test : public beast::unit_test::Suite
             jvParams[jss::ledger_hash] = ledgerHash;
             json::Value const jrr =
                 env.rpc("json", "ledger_entry", to_string(jvParams))[jss::result];
-            checkErrorValue(jrr, "entryNotFound", "Entry not found.");
+            checkErrorValue(jrr, "entryNotFound", RpcEntryNotFound, "Entry not found.");
         }
         {
             // Request a ticket using an account root entry.
@@ -2193,7 +2247,8 @@ class LedgerEntry_test : public beast::unit_test::Suite
             jvParams[jss::ledger_hash] = ledgerHash;
             json::Value const jrr =
                 env.rpc("json", "ledger_entry", to_string(jvParams))[jss::result];
-            checkErrorValue(jrr, "unexpectedLedgerType", "Unexpected ledger type.");
+            checkErrorValue(
+                jrr, "unexpectedLedgerType", RpcUnexpectedLedgerType, "Unexpected ledger type.");
         }
 
         {
@@ -2261,7 +2316,7 @@ class LedgerEntry_test : public beast::unit_test::Suite
             jvParams[jss::transaction_proposal][jss::ticket_seq] = ticketSeq + 1;
             jvParams[jss::ledger_hash] = ledgerHash;
             auto const jrr = env.rpc("json", "ledger_entry", to_string(jvParams))[jss::result];
-            checkErrorValue(jrr, "entryNotFound", "Entry not found.");
+            checkErrorValue(jrr, "entryNotFound", RpcEntryNotFound, "Entry not found.");
         }
         {
             // Lookup by an index of the wrong entry type.
@@ -2269,7 +2324,8 @@ class LedgerEntry_test : public beast::unit_test::Suite
             jvParams[jss::transaction_proposal] = to_string(keylet::account(target).key);
             jvParams[jss::ledger_hash] = ledgerHash;
             auto const jrr = env.rpc("json", "ledger_entry", to_string(jvParams))[jss::result];
-            checkErrorValue(jrr, "unexpectedLedgerType", "Unexpected ledger type.");
+            checkErrorValue(
+                jrr, "unexpectedLedgerType", RpcUnexpectedLedgerType, "Unexpected ledger type.");
         }
 
         {
@@ -2333,7 +2389,7 @@ class LedgerEntry_test : public beast::unit_test::Suite
             jvParams[jss::ledger_hash] = ledgerHash;
             json::Value const jrr =
                 env.rpc("json", "ledger_entry", to_string(jvParams))[jss::result];
-            checkErrorValue(jrr, "entryNotFound", "Entry not found.");
+            checkErrorValue(jrr, "entryNotFound", RpcEntryNotFound, "Entry not found.");
         }
         {
             // Malformed DID index
@@ -2455,7 +2511,7 @@ class LedgerEntry_test : public beast::unit_test::Suite
             jvParams[jss::ledger_hash] = ledgerHash;
             json::Value const jrr =
                 env.rpc("json", "ledger_entry", to_string(jvParams))[jss::result];
-            checkErrorValue(jrr, "entryNotFound", "Entry not found.");
+            checkErrorValue(jrr, "entryNotFound", RpcEntryNotFound, "Entry not found.");
         }
         {
             // Request the MPToken using its owner + mptIssuanceID.
@@ -2478,7 +2534,7 @@ class LedgerEntry_test : public beast::unit_test::Suite
             jvParams[jss::ledger_hash] = ledgerHash;
             json::Value const jrr =
                 env.rpc("json", "ledger_entry", to_string(jvParams))[jss::result];
-            checkErrorValue(jrr, "entryNotFound", "Entry not found.");
+            checkErrorValue(jrr, "entryNotFound", RpcEntryNotFound, "Entry not found.");
         }
         {
             // Malformed MPTIssuance index
@@ -2546,7 +2602,8 @@ class LedgerEntry_test : public beast::unit_test::Suite
                 "12F1F1F1F180D67377B2FAB292A31C922470326268D2B9B74CD1E582645B9A"
                 "DE";
             auto const jrr = env.rpc("json", "ledger_entry", to_string(params));
-            checkErrorValue(jrr[jss::result], "entryNotFound", "Entry not found.");
+            checkErrorValue(
+                jrr[jss::result], "entryNotFound", RpcEntryNotFound, "Entry not found.");
         }
         {
             // test basic malformed scenarios
@@ -2592,7 +2649,9 @@ class LedgerEntry_test : public beast::unit_test::Suite
         auto checkResult = [&](bool good,
                                json::Value const& jv,
                                json::StaticString const& expectedType,
-                               std::optional<std::string> const& expectedError = {}) {
+                               std::optional<std::string> const& expectedError = {},
+                               ErrorCodeI expectedCode = RpcEntryNotFound,
+                               std::string const& expectedMessage = "Entry not found.") {
             if (good)
             {
                 BEAST_EXPECTS(
@@ -2607,9 +2666,10 @@ class LedgerEntry_test : public beast::unit_test::Suite
             {
                 BEAST_EXPECTS(
                     jv.isObject() && jv.isMember(jss::result) &&
-                        jv[jss::result].isMember(jss::error) &&
                         !jv[jss::result].isMember(jss::node) &&
-                        jv[jss::result][jss::error] == expectedError.value_or("entryNotFound"),
+                        jv[jss::result][jss::error] == expectedError.value_or("entryNotFound") &&
+                        jv[jss::result][jss::error_code] == expectedCode &&
+                        jv[jss::result][jss::error_message] == expectedMessage,
                     to_string(jv));
             }
         };
@@ -2640,7 +2700,13 @@ class LedgerEntry_test : public beast::unit_test::Suite
                 params[jss::ledger_index] = jss::validated;
                 params[field] = json::ValueType::Null;
                 auto const jv = env.rpc("json", "ledger_entry", to_string(params));
-                checkResult(false, jv, expectedType, "malformedRequest");
+                checkResult(
+                    false,
+                    jv,
+                    expectedType,
+                    "malformedRequest",
+                    RpcInvalidParams,
+                    rpc::expectedFieldMessage(field, "hex string"));
                 BEAST_EXPECT(!jv[jss::result].isMember(jss::index));
             }
 
@@ -2650,7 +2716,13 @@ class LedgerEntry_test : public beast::unit_test::Suite
                 params[jss::ledger_index] = jss::validated;
                 params[field] = "arbitrary string";
                 auto const jv = env.rpc("json", "ledger_entry", to_string(params));
-                checkResult(false, jv, expectedType, "malformedRequest");
+                checkResult(
+                    false,
+                    jv,
+                    expectedType,
+                    "malformedRequest",
+                    RpcInvalidParams,
+                    rpc::expectedFieldMessage(field, "hex string"));
                 BEAST_EXPECT(!jv[jss::result].isMember(jss::index));
             }
 
@@ -2660,7 +2732,13 @@ class LedgerEntry_test : public beast::unit_test::Suite
                 params[jss::ledger_index] = jss::validated;
                 params[field] = false;
                 auto const jv = env.rpc("json", "ledger_entry", to_string(params));
-                checkResult(false, jv, expectedType, "invalidParams");
+                checkResult(
+                    false,
+                    jv,
+                    expectedType,
+                    "invalidParams",
+                    RpcInvalidParams,
+                    rpc::expectedFieldMessage(field, "true"));
                 BEAST_EXPECT(!jv[jss::result].isMember(jss::index));
             }
 
@@ -2672,7 +2750,8 @@ class LedgerEntry_test : public beast::unit_test::Suite
                 params[jss::ledger_index] = jss::validated;
                 params[field] = badKey;
                 auto const jv = env.rpc("json", "ledger_entry", to_string(params));
-                checkResult(false, jv, expectedType, "entryNotFound");
+                checkResult(
+                    false, jv, expectedType, "entryNotFound", RpcEntryNotFound, "Entry not found.");
                 BEAST_EXPECTS(jv[jss::result][jss::index] == badKey, to_string(jv));
             }
 
@@ -2683,7 +2762,13 @@ class LedgerEntry_test : public beast::unit_test::Suite
                 params[jss::index] = field;
                 params[jss::api_version] = 2;
                 auto const jv = env.rpc("json", "ledger_entry", to_string(params));
-                checkResult(false, jv, expectedType, "malformedRequest");
+                checkResult(
+                    false,
+                    jv,
+                    expectedType,
+                    "malformedRequest",
+                    RpcInvalidParams,
+                    rpc::expectedFieldMessage(jss::index, "hex string"));
                 BEAST_EXPECT(!jv[jss::result].isMember(jss::index));
             }
 
@@ -2722,7 +2807,13 @@ class LedgerEntry_test : public beast::unit_test::Suite
                 params[jss::index] = field;
                 params[jss::api_version] = 2;
                 auto const jv = env.rpc("json", "ledger_entry", to_string(params));
-                checkResult(false, jv, expectedType, "malformedRequest");
+                checkResult(
+                    false,
+                    jv,
+                    expectedType,
+                    "malformedRequest",
+                    RpcInvalidParams,
+                    rpc::expectedFieldMessage(jss::index, "hex string"));
                 BEAST_EXPECT(!jv[jss::result].isMember(jss::index));
             }
 
@@ -2787,7 +2878,9 @@ class LedgerEntry_test : public beast::unit_test::Suite
         auto checkResult = [&](bool good,
                                json::Value const& jv,
                                int expectedCount,
-                               std::optional<std::string> const& expectedError = {}) {
+                               std::optional<std::string> const& expectedError = {},
+                               ErrorCodeI expectedCode = RpcEntryNotFound,
+                               std::string const& expectedMessage = "Entry not found.") {
             if (good)
             {
                 BEAST_EXPECTS(
@@ -2807,9 +2900,10 @@ class LedgerEntry_test : public beast::unit_test::Suite
             {
                 BEAST_EXPECTS(
                     jv.isObject() && jv.isMember(jss::result) &&
-                        jv[jss::result].isMember(jss::error) &&
                         !jv[jss::result].isMember(jss::node) &&
-                        jv[jss::result][jss::error] == expectedError.value_or("entryNotFound"),
+                        jv[jss::result][jss::error] == expectedError.value_or("entryNotFound") &&
+                        jv[jss::result][jss::error_code] == expectedCode &&
+                        jv[jss::result][jss::error_message] == expectedMessage,
                     to_string(jv));
             }
         };
@@ -2839,7 +2933,13 @@ class LedgerEntry_test : public beast::unit_test::Suite
                     params[jss::ledger_index] = jss::validated;
                     params[jss::hashes] = json::ValueType::Null;
                     auto jv = env.rpc("json", "ledger_entry", to_string(params));
-                    checkResult(false, jv, 0, "malformedRequest");
+                    checkResult(
+                        false,
+                        jv,
+                        0,
+                        "malformedRequest",
+                        RpcInvalidParams,
+                        rpc::expectedFieldMessage(jss::hashes, "hex string"));
                     BEAST_EXPECT(!jv[jss::result].isMember(jss::index));
                 }
 
@@ -2849,7 +2949,13 @@ class LedgerEntry_test : public beast::unit_test::Suite
                     params[jss::ledger_index] = jss::validated;
                     params[jss::hashes] = "arbitrary string";
                     auto const jv = env.rpc("json", "ledger_entry", to_string(params));
-                    checkResult(false, jv, 0, "malformedRequest");
+                    checkResult(
+                        false,
+                        jv,
+                        0,
+                        "malformedRequest",
+                        RpcInvalidParams,
+                        rpc::expectedFieldMessage(jss::hashes, "hex string"));
                     BEAST_EXPECT(!jv[jss::result].isMember(jss::index));
                 }
 
@@ -2859,7 +2965,13 @@ class LedgerEntry_test : public beast::unit_test::Suite
                     params[jss::ledger_index] = jss::validated;
                     params[jss::hashes] = "10";
                     auto const jv = env.rpc("json", "ledger_entry", to_string(params));
-                    checkResult(false, jv, 0, "malformedRequest");
+                    checkResult(
+                        false,
+                        jv,
+                        0,
+                        "malformedRequest",
+                        RpcInvalidParams,
+                        rpc::expectedFieldMessage(jss::hashes, "hex string"));
                     BEAST_EXPECT(!jv[jss::result].isMember(jss::index));
                 }
 
@@ -2869,7 +2981,13 @@ class LedgerEntry_test : public beast::unit_test::Suite
                     params[jss::ledger_index] = jss::validated;
                     params[jss::hashes] = false;
                     auto const jv = env.rpc("json", "ledger_entry", to_string(params));
-                    checkResult(false, jv, 0, "invalidParams");
+                    checkResult(
+                        false,
+                        jv,
+                        0,
+                        "invalidParams",
+                        RpcInvalidParams,
+                        rpc::expectedFieldMessage(jss::hashes, "true"));
                     BEAST_EXPECT(!jv[jss::result].isMember(jss::index));
                 }
 
@@ -2879,7 +2997,7 @@ class LedgerEntry_test : public beast::unit_test::Suite
                     params[jss::ledger_index] = jss::validated;
                     params[jss::hashes] = -1;
                     auto const jv = env.rpc("json", "ledger_entry", to_string(params));
-                    checkResult(false, jv, 0, "internal");
+                    checkResult(false, jv, 0, "internal", RpcInternal, "Internal error.");
                     BEAST_EXPECT(!jv[jss::result].isMember(jss::index));
                 }
 
@@ -2890,7 +3008,8 @@ class LedgerEntry_test : public beast::unit_test::Suite
                     params[jss::ledger_index] = jss::validated;
                     params[jss::hashes] = badKey;
                     auto const jv = env.rpc("json", "ledger_entry", to_string(params));
-                    checkResult(false, jv, 0, "entryNotFound");
+                    checkResult(
+                        false, jv, 0, "entryNotFound", RpcEntryNotFound, "Entry not found.");
                     BEAST_EXPECT(jv[jss::result][jss::index] == badKey);
                 }
 
@@ -3028,12 +3147,18 @@ class LedgerEntry_XChain_test : public beast::unit_test::Suite,
                                 public test::jtx::XChainBridgeObjects
 {
     void
-    checkErrorValue(json::Value const& jv, std::string const& err, std::string const& msg)
+    checkErrorValue(
+        json::Value const& jv,
+        std::string const& err,
+        ErrorCodeI code,
+        std::string const& msg)
     {
         if (BEAST_EXPECT(jv.isMember(jss::status)))
             BEAST_EXPECT(jv[jss::status] == "error");
         if (BEAST_EXPECT(jv.isMember(jss::error)))
             BEAST_EXPECT(jv[jss::error] == err);
+        if (BEAST_EXPECT(jv.isMember(jss::error_code)))
+            BEAST_EXPECT(jv[jss::error_code] == code);
         if (msg.empty())
         {
             BEAST_EXPECT(
@@ -3110,7 +3235,7 @@ class LedgerEntry_XChain_test : public beast::unit_test::Suite,
             json::Value const jrr =
                 mcEnv.rpc("json", "ledger_entry", to_string(jvParams))[jss::result];
 
-            checkErrorValue(jrr, "entryNotFound", "Entry not found.");
+            checkErrorValue(jrr, "entryNotFound", RpcEntryNotFound, "Entry not found.");
         }
         {
             // create two claim ids and verify that the bridge counter was
@@ -3297,7 +3422,7 @@ class LedgerEntry_XChain_test : public beast::unit_test::Suite,
                     [jss::xchain_owned_create_account_claim_id] = 1;
             json::Value const jrr =
                 scEnv.rpc("json", "ledger_entry", to_string(jvParams))[jss::result];
-            checkErrorValue(jrr, "entryNotFound", "Entry not found.");
+            checkErrorValue(jrr, "entryNotFound", RpcEntryNotFound, "Entry not found.");
         }
     }
 

src/test/rpc/LedgerHeader_test.cpp

@@ -3,6 +3,7 @@
 
 #include <xrpl/beast/unit_test/suite.h>
 #include <xrpl/json/json_value.h>
+#include <xrpl/protocol/ErrorCodes.h>
 #include <xrpl/protocol/jss.h>
 
 namespace xrpl {
@@ -53,8 +54,10 @@ class LedgerHeader_test : public beast::unit_test::Suite
         json::Value params{json::ValueType::Object};
         params[jss::api_version] = 2;
         auto const result = env.client().invoke("ledger_header", params)[jss::result];
-        BEAST_EXPECT(result[jss::error] == "unknownCmd");
         BEAST_EXPECT(result[jss::status] == "error");
+        BEAST_EXPECT(result[jss::error] == "unknownCmd");
+        BEAST_EXPECT(result[jss::error_code] == RpcUnknownCommand);
+        BEAST_EXPECT(result[jss::error_message] == "Unknown method.");
     }
 
 public:

src/test/rpc/LedgerRPC_test.cpp

@@ -37,12 +37,18 @@ namespace xrpl::test {
 class LedgerRPC_test : public beast::unit_test::Suite
 {
     void
-    checkErrorValue(json::Value const& jv, std::string const& err, std::string const& msg)
+    checkErrorValue(
+        json::Value const& jv,
+        std::string const& err,
+        ErrorCodeI code,
+        std::string const& msg)
     {
         if (BEAST_EXPECT(jv.isMember(jss::status)))
             BEAST_EXPECT(jv[jss::status] == "error");
         if (BEAST_EXPECT(jv.isMember(jss::error)))
             BEAST_EXPECT(jv[jss::error] == err);
+        if (BEAST_EXPECT(jv.isMember(jss::error_code)))
+            BEAST_EXPECT(jv[jss::error_code] == code);
         if (msg.empty())
         {
             BEAST_EXPECT(
@@ -139,7 +145,10 @@ class LedgerRPC_test : public beast::unit_test::Suite
             jvParams[jss::ledger_index] = "potato";
             auto const jrr = env.rpc("json", "ledger", to_string(jvParams))[jss::result];
             checkErrorValue(
-                jrr, "invalidParams", "Invalid field 'ledger_index', not string or number.");
+                jrr,
+                "invalidParams",
+                RpcInvalidParams,
+                "Invalid field 'ledger_index', not string or number.");
         }
 
         {
@@ -148,7 +157,10 @@ class LedgerRPC_test : public beast::unit_test::Suite
             jvParams[jss::ledger_index] = -1;
             auto const jrr = env.rpc("json", "ledger", to_string(jvParams))[jss::result];
             checkErrorValue(
-                jrr, "invalidParams", "Invalid field 'ledger_index', not string or number.");
+                jrr,
+                "invalidParams",
+                RpcInvalidParams,
+                "Invalid field 'ledger_index', not string or number.");
         }
 
         {
@@ -156,13 +168,13 @@ class LedgerRPC_test : public beast::unit_test::Suite
             json::Value jvParams;
             jvParams[jss::ledger_index] = 10u;
             auto const jrr = env.rpc("json", "ledger", to_string(jvParams))[jss::result];
-            checkErrorValue(jrr, "lgrNotFound", "ledgerNotFound");
+            checkErrorValue(jrr, "lgrNotFound", RpcLgrNotFound, "ledgerNotFound");
         }
 
         {
             // unrecognized string arg -- error
             auto const jrr = env.rpc("ledger", "arbitrary_text")[jss::result];
-            checkErrorValue(jrr, "lgrNotFound", "ledgerNotFound");
+            checkErrorValue(jrr, "lgrNotFound", RpcLgrNotFound, "ledgerNotFound");
         }
 
         {
@@ -171,20 +183,21 @@ class LedgerRPC_test : public beast::unit_test::Suite
             jvParams[jss::ledger_index] = "validated";
             jvParams[jss::queue] = true;
             auto const jrr = env.rpc("json", "ledger", to_string(jvParams))[jss::result];
-            checkErrorValue(jrr, "invalidParams", "Invalid parameters.");
+            checkErrorValue(jrr, "invalidParams", RpcInvalidParams, "Invalid parameters.");
         }
 
         {
             // Request a ledger with a very large (double) sequence.
             auto const ret = env.rpc("json", "ledger", "{ \"ledger_index\" : 2e15 }");
-            BEAST_EXPECT(rpc::containsError(ret));
+            BEAST_EXPECT(ret[jss::error] == "invalidParams");
+            BEAST_EXPECT(ret[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(ret[jss::error_message] == "Invalid parameters.");
         }
 
         {
             // Request a ledger with very large (integer) sequence.
             auto const ret = env.rpc("json", "ledger", "{ \"ledger_index\" : 1000000000000000 }");
-            checkErrorValue(ret, "invalidParams", "Invalid parameters.");
+            checkErrorValue(ret, "invalidParams", RpcInvalidParams, "Invalid parameters.");
         }
 
         {
@@ -193,7 +206,7 @@ class LedgerRPC_test : public beast::unit_test::Suite
                 json::Value jvParams;
                 jvParams[field] = "blah";
                 auto const jrr = env.rpc("json", "ledger", to_string(jvParams))[jss::result];
-                checkErrorValue(jrr, "invalidParams", "Invalid parameters.");
+                checkErrorValue(jrr, "invalidParams", RpcInvalidParams, "Invalid parameters.");
             };
             testBooleanField(jss::full);
             testBooleanField(jss::accounts);
@@ -255,7 +268,8 @@ class LedgerRPC_test : public beast::unit_test::Suite
         jvParams[jss::ledger_index] = 1u;
         jvParams[jss::full] = true;
         auto const jrr = env.rpc("json", "ledger", to_string(jvParams))[jss::result];
-        checkErrorValue(jrr, "noPermission", "You don't have permission for this command.");
+        checkErrorValue(
+            jrr, "noPermission", RpcNoPermission, "You don't have permission for this command.");
     }
 
     void
@@ -422,6 +436,7 @@ class LedgerRPC_test : public beast::unit_test::Suite
             jvParams[jss::ledger] = "invalid";
             jrr = env.rpc("json", "ledger", to_string(jvParams))[jss::result];
             BEAST_EXPECT(jrr[jss::error] == "invalidParams");
+            BEAST_EXPECT(jrr[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(
                 jrr[jss::error_message] == "Invalid field 'ledger', not string or number.");
 
@@ -436,6 +451,7 @@ class LedgerRPC_test : public beast::unit_test::Suite
             jvParams[jss::ledger] = 20;
             jrr = env.rpc("json", "ledger", to_string(jvParams))[jss::result];
             BEAST_EXPECT(jrr[jss::error] == "lgrNotFound");
+            BEAST_EXPECT(jrr[jss::error_code] == RpcLgrNotFound);
             BEAST_EXPECT(jrr[jss::error_message] == "ledgerNotFound");
         }
 
@@ -455,12 +471,14 @@ class LedgerRPC_test : public beast::unit_test::Suite
             jvParams[jss::ledger_hash] = "DEADBEEF" + hash3;
             jrr = env.rpc("json", "ledger", to_string(jvParams))[jss::result];
             BEAST_EXPECT(jrr[jss::error] == "invalidParams");
+            BEAST_EXPECT(jrr[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(jrr[jss::error_message] == "Invalid field 'ledger_hash', not hex string.");
 
             // request with non-string ledger_hash
             jvParams[jss::ledger_hash] = 2;
             jrr = env.rpc("json", "ledger", to_string(jvParams))[jss::result];
             BEAST_EXPECT(jrr[jss::error] == "invalidParams");
+            BEAST_EXPECT(jrr[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(jrr[jss::error_message] == "Invalid field 'ledger_hash', not hex string.");
 
             // malformed (non hex) hash
@@ -469,6 +487,7 @@ class LedgerRPC_test : public beast::unit_test::Suite
                 "7F2775F2F7485BB37307984C3C0F2340";
             jrr = env.rpc("json", "ledger", to_string(jvParams))[jss::result];
             BEAST_EXPECT(jrr[jss::error] == "invalidParams");
+            BEAST_EXPECT(jrr[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(jrr[jss::error_message] == "Invalid field 'ledger_hash', not hex string.");
 
             // properly formed, but just doesn't exist
@@ -477,6 +496,7 @@ class LedgerRPC_test : public beast::unit_test::Suite
                 "5A75FD71FC3FD6F36FEB803C5F1D812D";
             jrr = env.rpc("json", "ledger", to_string(jvParams))[jss::result];
             BEAST_EXPECT(jrr[jss::error] == "lgrNotFound");
+            BEAST_EXPECT(jrr[jss::error_code] == RpcLgrNotFound);
             BEAST_EXPECT(jrr[jss::error_message] == "ledgerNotFound");
         }
 
@@ -506,6 +526,7 @@ class LedgerRPC_test : public beast::unit_test::Suite
             jvParams[jss::ledger_index] = "invalid";
             jrr = env.rpc("json", "ledger", to_string(jvParams))[jss::result];
             BEAST_EXPECT(jrr[jss::error] == "invalidParams");
+            BEAST_EXPECT(jrr[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(
                 jrr[jss::error_message] == "Invalid field 'ledger_index', not string or number.");
 
@@ -524,6 +545,7 @@ class LedgerRPC_test : public beast::unit_test::Suite
             jvParams[jss::ledger_index] = 7;
             jrr = env.rpc("json", "ledger", to_string(jvParams))[jss::result];
             BEAST_EXPECT(jrr[jss::error] == "lgrNotFound");
+            BEAST_EXPECT(jrr[jss::error_code] == RpcLgrNotFound);
             BEAST_EXPECT(jrr[jss::error_message] == "ledgerNotFound");
         }
     }

src/test/rpc/LedgerRequest_test.cpp

@@ -43,21 +43,24 @@ public:
             // arbitrary text is converted to 0.
             auto const result = env.rpc("ledger_request", "arbitrary_text");
             BEAST_EXPECT(
-                rpc::containsError(result[jss::result]) &&
+                result[jss::result][jss::error] == "invalidParams" &&
+                result[jss::result][jss::error_code] == RpcInvalidParams &&
                 result[jss::result][jss::error_message] == "Ledger index too small");
         }
 
         {
             auto const result = env.rpc("ledger_request", "-1");
             BEAST_EXPECT(
-                rpc::containsError(result[jss::result]) &&
+                result[jss::result][jss::error] == "invalidParams" &&
+                result[jss::result][jss::error_code] == RpcInvalidParams &&
                 result[jss::result][jss::error_message] == "Ledger index too small");
         }
 
         {
             auto const result = env.rpc("ledger_request", "0");
             BEAST_EXPECT(
-                rpc::containsError(result[jss::result]) &&
+                result[jss::result][jss::error] == "invalidParams" &&
+                result[jss::result][jss::error_code] == RpcInvalidParams &&
                 result[jss::result][jss::error_message] == "Ledger index too small");
         }
 
@@ -112,7 +115,8 @@ public:
             auto const result = env.rpc("ledger_request", ledgerHash);
 
             BEAST_EXPECT(
-                rpc::containsError(result[jss::result]) &&
+                result[jss::result][jss::error] == "invalidParams" &&
+                result[jss::result][jss::error_code] == RpcInvalidParams &&
                 result[jss::result][jss::error_message] ==
                     "Invalid field 'ledger_hash', not hex string.");
         }
@@ -130,14 +134,16 @@ public:
         {
             auto const result = env.rpc("ledger_request", "4");
             BEAST_EXPECT(
-                rpc::containsError(result[jss::result]) &&
+                result[jss::result][jss::error] == "invalidParams" &&
+                result[jss::result][jss::error_code] == RpcInvalidParams &&
                 result[jss::result][jss::error_message] == "Ledger index too large");
         }
 
         {
             auto const result = env.rpc("ledger_request", "5");
             BEAST_EXPECT(
-                rpc::containsError(result[jss::result]) &&
+                result[jss::result][jss::error] == "invalidParams" &&
+                result[jss::result][jss::error_code] == RpcInvalidParams &&
                 result[jss::result][jss::error_message] == "Ledger index too large");
         }
     }
@@ -236,8 +242,9 @@ public:
             "8FE8592EF22FBC2E8C774C7A1ED76AA3FCE64BED17D748CBA9AFDF7072FE36C7");
 
         result = env.rpc("ledger_request", "6")[jss::result];
-        BEAST_EXPECT(result[jss::error] == "invalidParams");
         BEAST_EXPECT(result[jss::status] == "error");
+        BEAST_EXPECT(result[jss::error] == "invalidParams");
+        BEAST_EXPECT(result[jss::error_code] == RpcInvalidParams);
         BEAST_EXPECT(result[jss::error_message] == "Ledger index too large");
     }
 
@@ -259,8 +266,9 @@ public:
             jvParams[jss::ledger_index] = "1";
             auto const result =
                 env.rpc("json", "ledger_request", jvParams.toStyledString())[jss::result];
-            BEAST_EXPECT(result[jss::error] == "invalidParams");
             BEAST_EXPECT(result[jss::status] == "error");
+            BEAST_EXPECT(result[jss::error] == "invalidParams");
+            BEAST_EXPECT(result[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(
                 result[jss::error_message] ==
                 "Exactly one of 'ledger_hash' or 'ledger_index' can be "
@@ -272,8 +280,9 @@ public:
             jvParams[jss::ledger_index] = "index";
             auto const result =
                 env.rpc("json", "ledger_request", jvParams.toStyledString())[jss::result];
-            BEAST_EXPECT(result[jss::error] == "invalidParams");
             BEAST_EXPECT(result[jss::status] == "error");
+            BEAST_EXPECT(result[jss::error] == "invalidParams");
+            BEAST_EXPECT(result[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(result[jss::error_message] == "Invalid field 'ledger_index', not number.");
         }
 
@@ -285,11 +294,13 @@ public:
         if (apiVersion == 1)
         {
             BEAST_EXPECT(result[jss::error] == "noCurrent");
+            BEAST_EXPECT(result[jss::error_code] == RpcNoCurrent);
             BEAST_EXPECT(result[jss::error_message] == "Current ledger is unavailable.");
         }
         else
         {
             BEAST_EXPECT(result[jss::error] == "notSynced");
+            BEAST_EXPECT(result[jss::error_code] == RpcNotSynced);
             BEAST_EXPECT(result[jss::error_message] == "Not synced to the network.");
         }
     }

src/test/rpc/ManifestRPC_test.cpp

@@ -7,6 +7,7 @@
 
 #include <xrpl/beast/unit_test/suite.h>
 #include <xrpl/config/Constants.h>
+#include <xrpl/protocol/ErrorCodes.h>
 #include <xrpl/protocol/jss.h>
 
 #include <memory>
@@ -27,6 +28,8 @@ public:
         {
             // manifest with no public key
             auto const info = env.rpc("json", "manifest", "{ }");
+            BEAST_EXPECT(info[jss::result][jss::error] == "invalidParams");
+            BEAST_EXPECT(info[jss::result][jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(info[jss::result][jss::error_message] == "Missing field 'public_key'.");
         }
         {
@@ -36,6 +39,8 @@ public:
                 "manifest",
                 "{ \"public_key\": "
                 "\"abcdef12345\"}");
+            BEAST_EXPECT(info[jss::result][jss::error] == "invalidParams");
+            BEAST_EXPECT(info[jss::result][jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(info[jss::result][jss::error_message] == "Invalid parameters.");
         }
     }

src/test/rpc/NoRippleCheck_test.cpp

@@ -19,6 +19,7 @@
 #include <xrpl/beast/unit_test/suite.h>
 #include <xrpl/json/json_value.h>
 #include <xrpl/json/to_string.h>
+#include <xrpl/protocol/ErrorCodes.h>
 #include <xrpl/protocol/SecretKey.h>
 #include <xrpl/protocol/TxFlags.h>
 #include <xrpl/protocol/jss.h>
@@ -49,6 +50,7 @@ class NoRippleCheck_test : public beast::unit_test::Suite
         {  // missing account field
             auto const result = env.rpc("json", "noripple_check", "{}")[jss::result];
             BEAST_EXPECT(result[jss::error] == "invalidParams");
+            BEAST_EXPECT(result[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(result[jss::error_message] == "Missing field 'account'.");
         }
 
@@ -57,6 +59,7 @@ class NoRippleCheck_test : public beast::unit_test::Suite
             params[jss::account] = alice.human();
             auto const result = env.rpc("json", "noripple_check", to_string(params))[jss::result];
             BEAST_EXPECT(result[jss::error] == "invalidParams");
+            BEAST_EXPECT(result[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(result[jss::error_message] == "Missing field 'role'.");
         }
 
@@ -68,6 +71,7 @@ class NoRippleCheck_test : public beast::unit_test::Suite
                 params[jss::role] = "user";
                 auto jrr = env.rpc("json", "noripple_check", to_string(params))[jss::result];
                 BEAST_EXPECT(jrr[jss::error] == "invalidParams");
+                BEAST_EXPECT(jrr[jss::error_code] == RpcInvalidParams);
                 BEAST_EXPECT(jrr[jss::error_message] == "Invalid field 'account'.");
             };
 
@@ -85,6 +89,7 @@ class NoRippleCheck_test : public beast::unit_test::Suite
             params[jss::role] = "not_a_role";
             auto const result = env.rpc("json", "noripple_check", to_string(params))[jss::result];
             BEAST_EXPECT(result[jss::error] == "invalidParams");
+            BEAST_EXPECT(result[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(result[jss::error_message] == "Invalid field 'role'.");
         }
 
@@ -95,6 +100,7 @@ class NoRippleCheck_test : public beast::unit_test::Suite
             params[jss::limit] = -1;
             auto const result = env.rpc("json", "noripple_check", to_string(params))[jss::result];
             BEAST_EXPECT(result[jss::error] == "invalidParams");
+            BEAST_EXPECT(result[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(
                 result[jss::error_message] == "Invalid field 'limit', not unsigned integer.");
         }
@@ -106,6 +112,7 @@ class NoRippleCheck_test : public beast::unit_test::Suite
             params[jss::ledger_hash] = 1;
             auto const result = env.rpc("json", "noripple_check", to_string(params))[jss::result];
             BEAST_EXPECT(result[jss::error] == "invalidParams");
+            BEAST_EXPECT(result[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(
                 result[jss::error_message] == "Invalid field 'ledger_hash', not hex string.");
         }
@@ -117,6 +124,7 @@ class NoRippleCheck_test : public beast::unit_test::Suite
             params[jss::ledger] = "current";
             auto const result = env.rpc("json", "noripple_check", to_string(params))[jss::result];
             BEAST_EXPECT(result[jss::error] == "actNotFound");
+            BEAST_EXPECT(result[jss::error_code] == RpcActNotFound);
             BEAST_EXPECT(result[jss::error_message] == "Account not found.");
         }
 
@@ -129,6 +137,7 @@ class NoRippleCheck_test : public beast::unit_test::Suite
             params[jss::transactions] = true;
             auto const result = env.rpc("json", "noripple_check", to_string(params))[jss::result];
             BEAST_EXPECT(result[jss::error] == "actMalformed");
+            BEAST_EXPECT(result[jss::error_code] == RpcActMalformed);
             BEAST_EXPECT(result[jss::error_message] == "Account malformed.");
             // The changelog promises malformed-account responses carry
             // neither `transactions` nor any ledger metadata.
@@ -147,6 +156,7 @@ class NoRippleCheck_test : public beast::unit_test::Suite
             params[jss::ledger_hash] = "ABCDEF";
             auto const result = env.rpc("json", "noripple_check", to_string(params))[jss::result];
             BEAST_EXPECT(result[jss::error] == "invalidParams");
+            BEAST_EXPECT(result[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(
                 result[jss::error_message] ==
                 "Exactly one of 'ledger', 'ledger_hash', or 'ledger_index' can "
@@ -161,6 +171,7 @@ class NoRippleCheck_test : public beast::unit_test::Suite
             params[jss::ledger] = json::ValueType::Object;
             auto const result = env.rpc("json", "noripple_check", to_string(params))[jss::result];
             BEAST_EXPECT(result[jss::error] == "invalidParams");
+            BEAST_EXPECT(result[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(
                 result[jss::error_message] == "Invalid field 'ledger', not string or number.");
         }

src/test/rpc/NoRipple_test.cpp

@@ -14,6 +14,7 @@
 #include <xrpl/json/json_value.h>
 #include <xrpl/json/to_string.h>
 #include <xrpl/protocol/ApiVersion.h>
+#include <xrpl/protocol/ErrorCodes.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/TER.h>
 #include <xrpl/protocol/TxFlags.h>
@@ -256,6 +257,9 @@ public:
                 else
                 {
                     BEAST_EXPECT(lines[jss::result][jss::error] == "invalidParams");
+                    BEAST_EXPECT(lines[jss::result][jss::error_code] == RpcInvalidParams);
+                    BEAST_EXPECT(
+                        lines[jss::result][jss::error_message] == "Invalid field 'transactions'.");
                 }
             }
         }

src/test/rpc/OwnerInfo_test.cpp

@@ -10,6 +10,7 @@
 #include <xrpl/json/json_value.h>
 #include <xrpl/json/to_string.h>
 #include <xrpl/protocol/AccountID.h>
+#include <xrpl/protocol/ErrorCodes.h>
 #include <xrpl/protocol/SField.h>
 #include <xrpl/protocol/STAmount.h>
 #include <xrpl/protocol/UintTypes.h>
@@ -34,6 +35,7 @@ class OwnerInfo_test : public beast::unit_test::Suite
         {  // missing account field
             auto const result = env.rpc("json", "owner_info", "{}")[jss::result];
             BEAST_EXPECT(result[jss::error] == "invalidParams");
+            BEAST_EXPECT(result[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(result[jss::error_message] == "Missing field 'account'.");
         }
 
@@ -44,8 +46,10 @@ class OwnerInfo_test : public beast::unit_test::Suite
             if (BEAST_EXPECT(result.isMember(jss::accepted) && result.isMember(jss::current)))
             {
                 BEAST_EXPECT(result[jss::accepted][jss::error] == "actMalformed");
+                BEAST_EXPECT(result[jss::accepted][jss::error_code] == RpcActMalformed);
                 BEAST_EXPECT(result[jss::accepted][jss::error_message] == "Account malformed.");
                 BEAST_EXPECT(result[jss::current][jss::error] == "actMalformed");
+                BEAST_EXPECT(result[jss::current][jss::error_code] == RpcActMalformed);
                 BEAST_EXPECT(result[jss::current][jss::error_message] == "Account malformed.");
             }
         }

src/test/rpc/Simulate_test.cpp

@@ -183,6 +183,8 @@ class Simulate_test : public beast::unit_test::Suite
             // No params
             json::Value const params = json::ValueType::Object;
             auto const resp = env.rpc("json", "simulate", to_string(params));
+            BEAST_EXPECT(resp[jss::result][jss::error] == "invalidParams");
+            BEAST_EXPECT(resp[jss::result][jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(
                 resp[jss::result][jss::error_message] ==
                 "Neither `tx_blob` nor `tx_json` included.");
@@ -194,6 +196,8 @@ class Simulate_test : public beast::unit_test::Suite
             params[jss::tx_blob] = "1200";
 
             auto const resp = env.rpc("json", "simulate", to_string(params));
+            BEAST_EXPECT(resp[jss::result][jss::error] == "invalidParams");
+            BEAST_EXPECT(resp[jss::result][jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(
                 resp[jss::result][jss::error_message] ==
                 "Can only include one of `tx_blob` and `tx_json`.");
@@ -204,6 +208,8 @@ class Simulate_test : public beast::unit_test::Suite
             params[jss::tx_blob] = "1200";
             params[jss::binary] = "100";
             auto const resp = env.rpc("json", "simulate", to_string(params));
+            BEAST_EXPECT(resp[jss::result][jss::error] == "invalidParams");
+            BEAST_EXPECT(resp[jss::result][jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(resp[jss::result][jss::error_message] == "Invalid field 'binary'.");
         }
         {
@@ -212,6 +218,8 @@ class Simulate_test : public beast::unit_test::Suite
             params[jss::tx_blob] = "12";
 
             auto const resp = env.rpc("json", "simulate", to_string(params));
+            BEAST_EXPECT(resp[jss::result][jss::error] == "invalidParams");
+            BEAST_EXPECT(resp[jss::result][jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(resp[jss::result][jss::error_message] == "Invalid field 'tx_blob'.");
         }
         {
@@ -220,6 +228,8 @@ class Simulate_test : public beast::unit_test::Suite
             params[jss::tx_json] = json::ValueType::Object;
 
             auto const resp = env.rpc("json", "simulate", to_string(params));
+            BEAST_EXPECT(resp[jss::result][jss::error] == "invalidParams");
+            BEAST_EXPECT(resp[jss::result][jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(
                 resp[jss::result][jss::error_message] == "Missing field 'tx.TransactionType'.");
         }
@@ -231,6 +241,8 @@ class Simulate_test : public beast::unit_test::Suite
             params[jss::tx_json] = txJson;
 
             auto const resp = env.rpc("json", "simulate", to_string(params));
+            BEAST_EXPECT(resp[jss::result][jss::error] == "invalidParams");
+            BEAST_EXPECT(resp[jss::result][jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(resp[jss::result][jss::error_message] == "Missing field 'tx.Account'.");
         }
         {
@@ -239,6 +251,8 @@ class Simulate_test : public beast::unit_test::Suite
             params[jss::tx_blob] = "";
 
             auto const resp = env.rpc("json", "simulate", to_string(params));
+            BEAST_EXPECT(resp[jss::result][jss::error] == "invalidParams");
+            BEAST_EXPECT(resp[jss::result][jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(resp[jss::result][jss::error_message] == "Invalid field 'tx_blob'.");
         }
         {
@@ -247,6 +261,8 @@ class Simulate_test : public beast::unit_test::Suite
             params[jss::tx_blob] = 1.1;
 
             auto const resp = env.rpc("json", "simulate", to_string(params));
+            BEAST_EXPECT(resp[jss::result][jss::error] == "invalidParams");
+            BEAST_EXPECT(resp[jss::result][jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(resp[jss::result][jss::error_message] == "Invalid field 'tx_blob'.");
         }
         {
@@ -255,6 +271,8 @@ class Simulate_test : public beast::unit_test::Suite
             params[jss::tx_json] = "";
 
             auto const resp = env.rpc("json", "simulate", to_string(params));
+            BEAST_EXPECT(resp[jss::result][jss::error] == "invalidParams");
+            BEAST_EXPECT(resp[jss::result][jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(
                 resp[jss::result][jss::error_message] == "Invalid field 'tx_json', not object.");
         }
@@ -267,6 +285,8 @@ class Simulate_test : public beast::unit_test::Suite
             txJson[jss::Account] = env.master.human();
             params[jss::tx_json] = txJson;
             auto const resp = env.rpc("json", "simulate", to_string(params));
+            BEAST_EXPECT(resp[jss::result][jss::error] == "invalidParams");
+            BEAST_EXPECT(resp[jss::result][jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(resp[jss::result][jss::error_message] == "Invalid field 'seed'.");
         }
         {
@@ -278,6 +298,8 @@ class Simulate_test : public beast::unit_test::Suite
             txJson[jss::Account] = env.master.human();
             params[jss::tx_json] = txJson;
             auto const resp = env.rpc("json", "simulate", to_string(params));
+            BEAST_EXPECT(resp[jss::result][jss::error] == "invalidParams");
+            BEAST_EXPECT(resp[jss::result][jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(resp[jss::result][jss::error_message] == "Invalid field 'secret'.");
         }
         {
@@ -289,6 +311,8 @@ class Simulate_test : public beast::unit_test::Suite
             txJson[jss::Account] = env.master.human();
             params[jss::tx_json] = txJson;
             auto const resp = env.rpc("json", "simulate", to_string(params));
+            BEAST_EXPECT(resp[jss::result][jss::error] == "invalidParams");
+            BEAST_EXPECT(resp[jss::result][jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(resp[jss::result][jss::error_message] == "Invalid field 'seed_hex'.");
         }
         {
@@ -300,6 +324,8 @@ class Simulate_test : public beast::unit_test::Suite
             txJson[jss::Account] = env.master.human();
             params[jss::tx_json] = txJson;
             auto const resp = env.rpc("json", "simulate", to_string(params));
+            BEAST_EXPECT(resp[jss::result][jss::error] == "invalidParams");
+            BEAST_EXPECT(resp[jss::result][jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(resp[jss::result][jss::error_message] == "Invalid field 'passphrase'.");
         }
         {
@@ -311,6 +337,9 @@ class Simulate_test : public beast::unit_test::Suite
             params[jss::tx_json] = txJson;
 
             auto const resp = env.rpc("json", "simulate", to_string(params));
+            BEAST_EXPECT(resp[jss::result][jss::error] == "invalidTransaction");
+            BEAST_EXPECT(!resp[jss::result].isMember(jss::error_code));
+            BEAST_EXPECT(resp[jss::result][jss::error_message].isNull());
             BEAST_EXPECT(
                 resp[jss::result][jss::error_exception] ==
                 "Field 'Destination' is required but missing.");
@@ -327,6 +356,7 @@ class Simulate_test : public beast::unit_test::Suite
             BEAST_EXPECTS(
                 resp[jss::result][jss::error] == "srcActMalformed",
                 resp[jss::result][jss::error].toStyledString());
+            BEAST_EXPECT(resp[jss::result][jss::error_code] == RpcSrcActMalformed);
             BEAST_EXPECT(resp[jss::result][jss::error_message] == "Invalid field 'tx.Account'.");
         }
         {
@@ -338,6 +368,8 @@ class Simulate_test : public beast::unit_test::Suite
             params[jss::tx_json] = txJson;
 
             auto const resp = env.rpc("json", "simulate", to_string(params));
+            BEAST_EXPECT(resp[jss::result][jss::error] == "srcActNotFound");
+            BEAST_EXPECT(resp[jss::result][jss::error_code] == RpcSrcActNotFound);
             BEAST_EXPECT(resp[jss::result][jss::error_message] == "Source account not found.");
         }
         {
@@ -350,6 +382,8 @@ class Simulate_test : public beast::unit_test::Suite
             params[jss::tx_json] = txJson;
 
             auto const resp = env.rpc("json", "simulate", to_string(params));
+            BEAST_EXPECT(resp[jss::result][jss::error] == "invalidParams");
+            BEAST_EXPECT(resp[jss::result][jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(resp[jss::result][jss::error_message] == "Invalid field 'tx.Signers'.");
         }
         {
@@ -363,6 +397,8 @@ class Simulate_test : public beast::unit_test::Suite
             params[jss::tx_json] = txJson;
 
             auto const resp = env.rpc("json", "simulate", to_string(params));
+            BEAST_EXPECT(resp[jss::result][jss::error] == "invalidParams");
+            BEAST_EXPECT(resp[jss::result][jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(resp[jss::result][jss::error_message] == "Invalid field 'tx.Signers[0]'.");
         }
         {
@@ -375,6 +411,8 @@ class Simulate_test : public beast::unit_test::Suite
             params[jss::tx_json] = txJson;
 
             auto const resp = env.rpc("json", "simulate", to_string(params));
+            BEAST_EXPECT(resp[jss::result][jss::error] == "invalidParams");
+            BEAST_EXPECT(resp[jss::result][jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(
                 resp[jss::result][jss::error_message] ==
                 "Invalid field 'SponsorSignature', not object.");
@@ -391,6 +429,8 @@ class Simulate_test : public beast::unit_test::Suite
             params[jss::tx_json] = txJson;
 
             auto const resp = env.rpc("json", "simulate", to_string(params));
+            BEAST_EXPECT(resp[jss::result][jss::error] == "invalidParams");
+            BEAST_EXPECT(resp[jss::result][jss::error_code] == RpcInvalidParams);
             BEAST_EXPECTS(
                 resp[jss::result][jss::error_message] ==
                     "Invalid field 'tx.SponsorSignature.Signers'.",
@@ -406,6 +446,8 @@ class Simulate_test : public beast::unit_test::Suite
             params[jss::tx_json] = txJson;
 
             auto const resp = env.rpc("json", "simulate", to_string(params));
+            BEAST_EXPECT(resp[jss::result][jss::error] == "invalidParams");
+            BEAST_EXPECT(resp[jss::result][jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(
                 resp[jss::result][jss::error_message] == "Field 'tx_json.foo' is unknown.");
         }
@@ -415,6 +457,8 @@ class Simulate_test : public beast::unit_test::Suite
             txJson[jss::TransactionType] = jss::AccountSet;
             txJson[jss::Account] = alice.human();
             auto const resp = env.rpc("simulate", to_string(txJson), "1");
+            BEAST_EXPECT(resp[jss::error] == "invalidParams");
+            BEAST_EXPECT(resp[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(resp[jss::error_message] == "Invalid parameters.");
         }
         {
@@ -427,6 +471,8 @@ class Simulate_test : public beast::unit_test::Suite
             params[jss::tx_json] = txJson;
 
             auto const resp = env.rpc("json", "simulate", to_string(params));
+            BEAST_EXPECT(resp[jss::result][jss::error] == "transactionSigned");
+            BEAST_EXPECT(resp[jss::result][jss::error_code] == RpcTxSigned);
             BEAST_EXPECT(
                 resp[jss::result][jss::error_message] == "Transaction should not be signed.");
         }
@@ -449,6 +495,8 @@ class Simulate_test : public beast::unit_test::Suite
             params[jss::tx_json] = txJson;
 
             auto const resp = env.rpc("json", "simulate", to_string(params));
+            BEAST_EXPECT(resp[jss::result][jss::error] == "transactionSigned");
+            BEAST_EXPECT(resp[jss::result][jss::error_code] == RpcTxSigned);
             BEAST_EXPECT(
                 resp[jss::result][jss::error_message] == "Transaction should not be signed.");
         }
@@ -462,6 +510,8 @@ class Simulate_test : public beast::unit_test::Suite
             params[jss::tx_json] = txJson;
 
             auto const resp = env.rpc("json", "simulate", to_string(params));
+            BEAST_EXPECT(resp[jss::result][jss::error] == "invalidParams");
+            BEAST_EXPECT(resp[jss::result][jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(
                 resp[jss::result][jss::error_message] ==
                 "tfInnerBatchTxn flag is not allowed on top-level transactions.");
@@ -530,6 +580,7 @@ class Simulate_test : public beast::unit_test::Suite
             {
                 auto const resp = simulate(env, tx);
                 BEAST_EXPECT(resp[jss::error] == "noPermission");
+                BEAST_EXPECT(resp[jss::error_code] == RpcNoPermission);
                 BEAST_EXPECT(
                     resp[jss::error_message] ==
                     "WASM transactions are only supported in admin mode.");
@@ -559,7 +610,10 @@ class Simulate_test : public beast::unit_test::Suite
 
         using namespace jtx;
 
+        // Pin the reference fee so the asserted error message doesn't depend on
+        // UNIT_TEST_REFERENCE_FEE.
         Env env(*this, envconfig([](std::unique_ptr<Config> cfg) {
+            cfg->fees.referenceFee = 10;
             cfg->section(Sections::kTransactionQueue).set(Keys::kMinimumTxnInLedgerStandalone, "3");
             return cfg;
         }));
@@ -579,11 +633,10 @@ class Simulate_test : public beast::unit_test::Suite
 
             auto const resp = env.rpc("json", "simulate", to_string(params));
             auto const result = resp[jss::result];
-            if (BEAST_EXPECT(result.isMember(jss::error)))
-            {
-                BEAST_EXPECT(result[jss::error] == "highFee");
-                BEAST_EXPECT(result[jss::error_code] == RpcHighFee);
-            }
+            BEAST_EXPECT(result[jss::error] == "highFee");
+            BEAST_EXPECT(result[jss::error_code] == RpcHighFee);
+            BEAST_EXPECT(
+                result[jss::error_message] == "Fee of 8889 exceeds the requested tx limit of 100");
         }
     }
 
@@ -613,6 +666,7 @@ class Simulate_test : public beast::unit_test::Suite
         params[jss::tx_json] = jt.jv;
         auto const resp = env.rpc("json", "simulate", to_string(params));
         BEAST_EXPECT(resp[jss::result][jss::error] == "notImpl");
+        BEAST_EXPECT(resp[jss::result][jss::error_code] == RpcNotImpl);
         BEAST_EXPECT(resp[jss::result][jss::error_message] == "Not implemented.");
     }
 

src/test/rpc/Submit_test.cpp

@@ -8,6 +8,7 @@
 #include <xrpl/beast/unit_test/suite.h>
 #include <xrpl/json/json_value.h>
 #include <xrpl/json/to_string.h>
+#include <xrpl/protocol/ErrorCodes.h>
 #include <xrpl/protocol/Seed.h>
 #include <xrpl/protocol/jss.h>
 
@@ -39,6 +40,7 @@ public:
                 params[jss::fail_hard] = param;
                 auto const jrr = env.rpc("json", "submit", to_string(params))[jss::result];
                 BEAST_EXPECT(jrr[jss::error] == "invalidParams");
+                BEAST_EXPECT(jrr[jss::error_code] == RpcInvalidParams);
                 BEAST_EXPECT(jrr[jss::error_message] == "Invalid field 'fail_hard', not boolean.");
             }
 
@@ -50,6 +52,7 @@ public:
                 params[jss::fail_hard] = param;
                 auto const jrr = env.rpc("json", "submit", to_string(params))[jss::result];
                 BEAST_EXPECT(jrr[jss::error] == "invalidParams");
+                BEAST_EXPECT(jrr[jss::error_code] == RpcInvalidParams);
                 BEAST_EXPECT(jrr[jss::error_message] == "Invalid field 'fail_hard', not boolean.");
             }
         };

src/test/rpc/Subscribe_test.cpp

@@ -31,6 +31,7 @@
 #include <xrpl/json/json_value.h>
 #include <xrpl/json/to_string.h>
 #include <xrpl/protocol/AccountID.h>
+#include <xrpl/protocol/ErrorCodes.h>
 #include <xrpl/protocol/Feature.h>
 #include <xrpl/protocol/Fees.h>
 #include <xrpl/protocol/Indexes.h>
@@ -621,6 +622,7 @@ public:
         {
             auto const jr = env.rpc("json", method, "{}")[jss::result];
             BEAST_EXPECT(jr[jss::error] == "invalidParams");
+            BEAST_EXPECT(jr[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(jr[jss::error_message] == "Invalid parameters.");
         }
 
@@ -633,6 +635,7 @@ public:
             if (subscribe)
             {
                 BEAST_EXPECT(jr[jss::error] == "invalidParams");
+                BEAST_EXPECT(jr[jss::error_code] == RpcInvalidParams);
                 BEAST_EXPECT(jr[jss::error_message] == "Failed to parse url.");
             }
             // else TODO: why isn't this an error for unsubscribe ?
@@ -646,6 +649,7 @@ public:
             if (subscribe)
             {
                 BEAST_EXPECT(jr[jss::error] == "invalidParams");
+                BEAST_EXPECT(jr[jss::error_code] == RpcInvalidParams);
                 BEAST_EXPECT(jr[jss::error_message] == "Only http and https is supported.");
             }
         }
@@ -656,6 +660,7 @@ public:
             jv[jss::url] = "no-url";
             auto const jr = envNonadmin.rpc("json", method, to_string(jv))[jss::result];
             BEAST_EXPECT(jr[jss::error] == "noPermission");
+            BEAST_EXPECT(jr[jss::error_code] == RpcNoPermission);
             BEAST_EXPECT(jr[jss::error_message] == "You don't have permission for this command.");
         }
 
@@ -677,6 +682,7 @@ public:
                 jv[f] = nonArray;
                 auto const jr = wsc->invoke(method, jv)[jss::result];
                 BEAST_EXPECT(jr[jss::error] == "invalidParams");
+                BEAST_EXPECT(jr[jss::error_code] == RpcInvalidParams);
                 BEAST_EXPECT(jr[jss::error_message] == "Invalid parameters.");
             }
 
@@ -685,6 +691,7 @@ public:
                 jv[f] = json::ValueType::Array;
                 auto const jr = wsc->invoke(method, jv)[jss::result];
                 BEAST_EXPECT(jr[jss::error] == "actMalformed");
+                BEAST_EXPECT(jr[jss::error_code] == RpcActMalformed);
                 BEAST_EXPECT(jr[jss::error_message] == "Account malformed.");
             }
         }
@@ -695,6 +702,7 @@ public:
             jv[jss::mpt_issuances] = nonArray;
             auto jr = wsc->invoke(method, jv)[jss::result];
             BEAST_EXPECT(jr[jss::error] == "invalidParams");
+            BEAST_EXPECT(jr[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(jr[jss::error_message] == "Invalid parameters.");
         }
 
@@ -704,6 +712,7 @@ public:
             jv[jss::mpt_issuances][0u] = 1;
             auto jr = wsc->invoke(method, jv)[jss::result];
             BEAST_EXPECT(jr[jss::error] == "invalidParams");
+            BEAST_EXPECT(jr[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(jr[jss::error_message] == "Invalid parameters.");
         }
 
@@ -713,6 +722,7 @@ public:
             jv[jss::mpt_issuances][0u] = "not-an-mpt-issuance-id";
             auto jr = wsc->invoke(method, jv)[jss::result];
             BEAST_EXPECT(jr[jss::error] == "invalidParams");
+            BEAST_EXPECT(jr[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(jr[jss::error_message] == "Invalid parameters.");
         }
 
@@ -722,6 +732,7 @@ public:
             jv[jss::mpt_issuances][0u] = "0123456789ABCDEF";
             auto jr = wsc->invoke(method, jv)[jss::result];
             BEAST_EXPECT(jr[jss::error] == "invalidParams");
+            BEAST_EXPECT(jr[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(jr[jss::error_message] == "Invalid parameters.");
         }
 
@@ -731,6 +742,7 @@ public:
             jv[jss::books] = nonArray;
             auto const jr = wsc->invoke(method, jv)[jss::result];
             BEAST_EXPECT(jr[jss::error] == "invalidParams");
+            BEAST_EXPECT(jr[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(jr[jss::error_message] == "Invalid parameters.");
         }
 
@@ -740,6 +752,7 @@ public:
             jv[jss::books][0u] = 1;
             auto const jr = wsc->invoke(method, jv)[jss::result];
             BEAST_EXPECT(jr[jss::error] == "invalidParams");
+            BEAST_EXPECT(jr[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(jr[jss::error_message] == "Invalid parameters.");
         }
 
@@ -752,6 +765,7 @@ public:
             auto const jr = wsc->invoke(method, jv)[jss::result];
 
             BEAST_EXPECT(jr[jss::error] == "srcCurMalformed");
+            BEAST_EXPECT(jr[jss::error_code] == RpcSrcCurMalformed);
             BEAST_EXPECT(jr[jss::error_message] == "Source currency is malformed.");
         }
 
@@ -764,6 +778,7 @@ public:
             jv[jss::books][0u][jss::taker_pays][jss::currency] = "ZZZZ";
             auto const jr = wsc->invoke(method, jv)[jss::result];
             BEAST_EXPECT(jr[jss::error] == "srcCurMalformed");
+            BEAST_EXPECT(jr[jss::error_code] == RpcSrcCurMalformed);
             BEAST_EXPECT(jr[jss::error_message] == "Source currency is malformed.");
         }
 
@@ -777,6 +792,7 @@ public:
             jv[jss::books][0u][jss::taker_pays][jss::issuer] = 1;
             auto const jr = wsc->invoke(method, jv)[jss::result];
             BEAST_EXPECT(jr[jss::error] == "srcIsrMalformed");
+            BEAST_EXPECT(jr[jss::error_code] == RpcSrcIsrMalformed);
             BEAST_EXPECT(jr[jss::error_message] == "Source issuer is malformed.");
         }
 
@@ -790,6 +806,7 @@ public:
             jv[jss::books][0u][jss::taker_pays][jss::issuer] = Account{"gateway"}.human() + "DEAD";
             auto const jr = wsc->invoke(method, jv)[jss::result];
             BEAST_EXPECT(jr[jss::error] == "srcIsrMalformed");
+            BEAST_EXPECT(jr[jss::error_code] == RpcSrcIsrMalformed);
             BEAST_EXPECT(jr[jss::error_message] == "Source issuer is malformed.");
         }
 
@@ -803,6 +820,7 @@ public:
             auto const jr = wsc->invoke(method, jv)[jss::result];
             // NOTE: this error is slightly incongruous with the equivalent source currency error
             BEAST_EXPECT(jr[jss::error] == "dstAmtMalformed");
+            BEAST_EXPECT(jr[jss::error_code] == RpcDstAmtMalformed);
             BEAST_EXPECT(
                 jr[jss::error_message] == "Destination amount/currency/issuer is malformed.");
         }
@@ -818,6 +836,7 @@ public:
             // NOTE: this error is slightly incongruous with the
             // equivalent source currency error
             BEAST_EXPECT(jr[jss::error] == "dstAmtMalformed");
+            BEAST_EXPECT(jr[jss::error_code] == RpcDstAmtMalformed);
             BEAST_EXPECT(
                 jr[jss::error_message] == "Destination amount/currency/issuer is malformed.");
         }
@@ -832,6 +851,7 @@ public:
             jv[jss::books][0u][jss::taker_gets][jss::issuer] = 1;
             auto const jr = wsc->invoke(method, jv)[jss::result];
             BEAST_EXPECT(jr[jss::error] == "dstIsrMalformed");
+            BEAST_EXPECT(jr[jss::error_code] == RpcDstIsrMalformed);
             BEAST_EXPECT(jr[jss::error_message] == "Destination issuer is malformed.");
         }
 
@@ -845,6 +865,7 @@ public:
             jv[jss::books][0u][jss::taker_gets][jss::issuer] = Account{"gateway"}.human() + "DEAD";
             auto const jr = wsc->invoke(method, jv)[jss::result];
             BEAST_EXPECT(jr[jss::error] == "dstIsrMalformed");
+            BEAST_EXPECT(jr[jss::error_code] == RpcDstIsrMalformed);
             BEAST_EXPECT(jr[jss::error_message] == "Destination issuer is malformed.");
         }
 
@@ -858,6 +879,7 @@ public:
                 Account{"gateway"}["USD"](1).value().getJson(JsonOptions::Values::IncludeDate);
             auto const jr = wsc->invoke(method, jv)[jss::result];
             BEAST_EXPECT(jr[jss::error] == "badMarket");
+            BEAST_EXPECT(jr[jss::error_code] == RpcBadMarket);
             BEAST_EXPECT(jr[jss::error_message] == "No such market.");
         }
 
@@ -867,6 +889,7 @@ public:
             jv[jss::streams] = nonArray;
             auto const jr = wsc->invoke(method, jv)[jss::result];
             BEAST_EXPECT(jr[jss::error] == "invalidParams");
+            BEAST_EXPECT(jr[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(jr[jss::error_message] == "Invalid parameters.");
         }
 
@@ -876,6 +899,7 @@ public:
             jv[jss::streams][0u] = 1;
             auto const jr = wsc->invoke(method, jv)[jss::result];
             BEAST_EXPECT(jr[jss::error] == "malformedStream");
+            BEAST_EXPECT(jr[jss::error_code] == RpcStreamMalformed);
             BEAST_EXPECT(jr[jss::error_message] == "Stream malformed.");
         }
 
@@ -885,6 +909,7 @@ public:
             jv[jss::streams][0u] = "not_a_stream";
             auto const jr = wsc->invoke(method, jv)[jss::result];
             BEAST_EXPECT(jr[jss::error] == "malformedStream");
+            BEAST_EXPECT(jr[jss::error_code] == RpcStreamMalformed);
             BEAST_EXPECT(jr[jss::error_message] == "Stream malformed.");
         }
 
@@ -901,6 +926,7 @@ public:
                 jv[jss::books][0u][jss::taker] = 1;
                 auto const jr = wsc->invoke(method, jv)[jss::result];
                 BEAST_EXPECTS(jr[jss::error] == "actMalformed", jr.toStyledString());
+                BEAST_EXPECT(jr[jss::error_code] == RpcActMalformed);
                 BEAST_EXPECT(jr[jss::error_message] == "Account malformed.");
             }
 
@@ -915,6 +941,7 @@ public:
                 jv[jss::books][0u][jss::taker] = "not_an_account";
                 auto const jr = wsc->invoke(method, jv)[jss::result];
                 BEAST_EXPECTS(jr[jss::error] == "actMalformed", jr.toStyledString());
+                BEAST_EXPECT(jr[jss::error_code] == RpcActMalformed);
                 BEAST_EXPECT(jr[jss::error_message] == "Account malformed.");
             }
 
@@ -929,6 +956,7 @@ public:
                 jv[jss::books][0u][jss::taker] = Account{"alice"}.human() + "DEAD";
                 auto const jr = wsc->invoke(method, jv)[jss::result];
                 BEAST_EXPECTS(jr[jss::error] == "actMalformed", jr.toStyledString());
+                BEAST_EXPECT(jr[jss::error_code] == RpcActMalformed);
                 BEAST_EXPECT(jr[jss::error_message] == "Account malformed.");
             }
         }
@@ -1784,6 +1812,7 @@ public:
         auto const jr =
             wsc->invoke("subscribe", accountsRequest(makeAccountStrings(6)))[jss::result];
         BEAST_EXPECT(jr[jss::error] == "invalidParams");
+        BEAST_EXPECT(jr[jss::error_code] == RpcInvalidParams);
         BEAST_EXPECT(jr[jss::error_message] == "Too many subscriptions for this connection.");
     }
 
@@ -1866,6 +1895,7 @@ public:
         {
             auto const jr = wsc->invoke("subscribe", req)[jss::result];
             BEAST_EXPECT(jr[jss::error] == "invalidParams");
+            BEAST_EXPECT(jr[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(jr[jss::error_message] == "Too many subscriptions for this connection.");
         }
 
@@ -1916,6 +1946,7 @@ public:
             auto const jr =
                 wsc->invoke("subscribe", accountHistoryRequest(alice.human()))[jss::result];
             BEAST_EXPECT(jr[jss::error] == "invalidParams");
+            BEAST_EXPECT(jr[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(jr[jss::error_message] == "Invalid parameters.");
             BEAST_EXPECT(jr[jss::error_message] != "Too many subscriptions for this connection.");
         }
@@ -1951,6 +1982,7 @@ public:
             auto const jr =
                 wsc->invoke("subscribe", accountHistoryRequest(bob.human()))[jss::result];
             BEAST_EXPECT(jr[jss::error] == "invalidParams");
+            BEAST_EXPECT(jr[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(jr[jss::error_message] == "Too many subscriptions for this connection.");
         }
     }
@@ -1974,6 +2006,7 @@ public:
             auto const jr = wsc->invoke(
                 "subscribe", mptIssuancesRequest(makeMPTIssuanceStrings(6)))[jss::result];
             BEAST_EXPECT(jr[jss::error] == "invalidParams");
+            BEAST_EXPECT(jr[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(jr[jss::error_message] == "Too many subscriptions for this connection.");
         }
 
@@ -2017,6 +2050,7 @@ public:
             auto const jr = wsc->invoke(
                 "subscribe", mptIssuancesRequest(makeMPTIssuanceStrings(1, 100)))[jss::result];
             BEAST_EXPECT(jr[jss::error] == "invalidParams");
+            BEAST_EXPECT(jr[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(jr[jss::error_message] == "Too many subscriptions for this connection.");
         }
     }
@@ -2041,6 +2075,7 @@ public:
             auto const jr = wsc->invoke(
                 "subscribe", mptIssuancesRequest(makeMPTIssuanceStrings(3)))[jss::result];
             BEAST_EXPECT(jr[jss::error] == "invalidParams");
+            BEAST_EXPECT(jr[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(jr[jss::error_message] == "Too many subscriptions for this connection.");
 
             // Two more issuances do fit the remaining allowance.
@@ -2062,6 +2097,7 @@ public:
             auto const jr =
                 wsc->invoke("subscribe", accountsRequest(makeAccountStrings(1)))[jss::result];
             BEAST_EXPECT(jr[jss::error] == "invalidParams");
+            BEAST_EXPECT(jr[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(jr[jss::error_message] == "Too many subscriptions for this connection.");
         }
     }

src/test/rpc/TransactionEntry_test.cpp

@@ -38,16 +38,20 @@ class TransactionEntry_test : public beast::unit_test::Suite
         {
             // no params
             auto const result = env.client().invoke("transaction_entry", {})[jss::result];
-            BEAST_EXPECT(result[jss::error] == "fieldNotFoundTransaction");
             BEAST_EXPECT(result[jss::status] == "error");
+            BEAST_EXPECT(result[jss::error] == "fieldNotFoundTransaction");
+            BEAST_EXPECT(!result.isMember(jss::error_code));
+            BEAST_EXPECT(result[jss::error_message].isNull());
         }
 
         {
             json::Value params{json::ValueType::Object};
             params[jss::ledger] = 20;
             auto const result = env.client().invoke("transaction_entry", params)[jss::result];
-            BEAST_EXPECT(result[jss::error] == "lgrNotFound");
             BEAST_EXPECT(result[jss::status] == "error");
+            BEAST_EXPECT(result[jss::error] == "lgrNotFound");
+            BEAST_EXPECT(result[jss::error_code] == RpcLgrNotFound);
+            BEAST_EXPECT(result[jss::error_message] == "ledgerNotFound");
         }
 
         {
@@ -55,8 +59,10 @@ class TransactionEntry_test : public beast::unit_test::Suite
             params[jss::ledger] = "current";
             params[jss::tx_hash] = "DEADBEEF";
             auto const result = env.client().invoke("transaction_entry", params)[jss::result];
-            BEAST_EXPECT(result[jss::error] == "notYetImplemented");
             BEAST_EXPECT(result[jss::status] == "error");
+            BEAST_EXPECT(result[jss::error] == "notYetImplemented");
+            BEAST_EXPECT(!result.isMember(jss::error_code));
+            BEAST_EXPECT(result[jss::error_message].isNull());
         }
 
         {
@@ -65,8 +71,10 @@ class TransactionEntry_test : public beast::unit_test::Suite
             params[jss::tx_hash] =
                 "E2FE8D4AF3FCC3944DDF6CD8CDDC5E3F0AD50863EF8919AFEF10CB6408CD4D05";
             auto const result = env.client().invoke("transaction_entry", params)[jss::result];
-            BEAST_EXPECT(result[jss::error] == "notYetImplemented");
             BEAST_EXPECT(result[jss::status] == "error");
+            BEAST_EXPECT(result[jss::error] == "notYetImplemented");
+            BEAST_EXPECT(!result.isMember(jss::error_code));
+            BEAST_EXPECT(result[jss::error_message].isNull());
             BEAST_EXPECT(result.isMember(jss::ledger_current_index));
             BEAST_EXPECT(!result.isMember(jss::ledger_hash));
             BEAST_EXPECT(result[jss::validated] == false);
@@ -78,8 +86,10 @@ class TransactionEntry_test : public beast::unit_test::Suite
             params[jss::tx_hash] = "DEADBEEF";
             auto const result = env.client().invoke("transaction_entry", params)[jss::result];
             BEAST_EXPECT(!result[jss::ledger_hash].asString().empty());
-            BEAST_EXPECT(result[jss::error] == "malformedRequest");
             BEAST_EXPECT(result[jss::status] == "error");
+            BEAST_EXPECT(result[jss::error] == "malformedRequest");
+            BEAST_EXPECT(!result.isMember(jss::error_code));
+            BEAST_EXPECT(result[jss::error_message].isNull());
         }
 
         for (auto const type : {json::ValueType::Object, json::ValueType::Array})
@@ -88,8 +98,10 @@ class TransactionEntry_test : public beast::unit_test::Suite
             params[jss::ledger] = "closed";
             params[jss::tx_hash] = json::Value{type};
             auto const result = env.client().invoke("transaction_entry", params)[jss::result];
-            BEAST_EXPECT(result[jss::error] == "malformedRequest");
             BEAST_EXPECT(result[jss::status] == "error");
+            BEAST_EXPECT(result[jss::error] == "malformedRequest");
+            BEAST_EXPECT(!result.isMember(jss::error_code));
+            BEAST_EXPECT(result[jss::error_message].isNull());
         }
 
         std::string const txHash{
@@ -100,58 +112,74 @@ class TransactionEntry_test : public beast::unit_test::Suite
             // No arguments
             json::Value const result{env.rpc("transaction_entry")};
             BEAST_EXPECT(result[jss::ledger_hash].asString().empty());
-            BEAST_EXPECT(result[jss::error] == "badSyntax");
             BEAST_EXPECT(result[jss::status] == "error");
+            BEAST_EXPECT(result[jss::error] == "badSyntax");
+            BEAST_EXPECT(result[jss::error_code] == RpcBadSyntax);
+            BEAST_EXPECT(result[jss::error_message] == "Syntax error.");
         }
 
         {
             // One argument
             json::Value const result{env.rpc("transaction_entry", txHash)};
-            BEAST_EXPECT(result[jss::error] == "badSyntax");
             BEAST_EXPECT(result[jss::status] == "error");
+            BEAST_EXPECT(result[jss::error] == "badSyntax");
+            BEAST_EXPECT(result[jss::error_code] == RpcBadSyntax);
+            BEAST_EXPECT(result[jss::error_message] == "Syntax error.");
         }
 
         {
             // First argument with too few characters
             json::Value const result{env.rpc("transaction_entry", txHash.substr(1), "closed")};
-            BEAST_EXPECT(result[jss::error] == "invalidParams");
             BEAST_EXPECT(result[jss::status] == "error");
+            BEAST_EXPECT(result[jss::error] == "invalidParams");
+            BEAST_EXPECT(result[jss::error_code] == RpcInvalidParams);
+            BEAST_EXPECT(result[jss::error_message] == "Invalid parameters.");
         }
 
         {
             // First argument with too many characters
             json::Value const result{env.rpc("transaction_entry", txHash + "A", "closed")};
-            BEAST_EXPECT(result[jss::error] == "invalidParams");
             BEAST_EXPECT(result[jss::status] == "error");
+            BEAST_EXPECT(result[jss::error] == "invalidParams");
+            BEAST_EXPECT(result[jss::error_code] == RpcInvalidParams);
+            BEAST_EXPECT(result[jss::error_message] == "Invalid parameters.");
         }
 
         {
             // Second argument not valid
             json::Value const result{env.rpc("transaction_entry", txHash, "closer")};
-            BEAST_EXPECT(result[jss::error] == "invalidParams");
             BEAST_EXPECT(result[jss::status] == "error");
+            BEAST_EXPECT(result[jss::error] == "invalidParams");
+            BEAST_EXPECT(result[jss::error_code] == RpcInvalidParams);
+            BEAST_EXPECT(result[jss::error_message] == "Invalid parameters.");
         }
 
         {
             // Ledger index of 0 is not valid
             json::Value const result{env.rpc("transaction_entry", txHash, "0")};
-            BEAST_EXPECT(result[jss::error] == "invalidParams");
             BEAST_EXPECT(result[jss::status] == "error");
+            BEAST_EXPECT(result[jss::error] == "invalidParams");
+            BEAST_EXPECT(result[jss::error_code] == RpcInvalidParams);
+            BEAST_EXPECT(result[jss::error_message] == "Invalid parameters.");
         }
 
         {
             // Three arguments
             json::Value const result{env.rpc("transaction_entry", txHash, "closed", "extra")};
-            BEAST_EXPECT(result[jss::error] == "badSyntax");
             BEAST_EXPECT(result[jss::status] == "error");
+            BEAST_EXPECT(result[jss::error] == "badSyntax");
+            BEAST_EXPECT(result[jss::error_code] == RpcBadSyntax);
+            BEAST_EXPECT(result[jss::error_message] == "Syntax error.");
         }
 
         {
             // Valid structure, but transaction not found.
             json::Value const result{env.rpc("transaction_entry", txHash, "closed")};
             BEAST_EXPECT(!result[jss::result][jss::ledger_hash].asString().empty());
-            BEAST_EXPECT(result[jss::result][jss::error] == "transactionNotFound");
             BEAST_EXPECT(result[jss::result][jss::status] == "error");
+            BEAST_EXPECT(result[jss::result][jss::error] == "transactionNotFound");
+            BEAST_EXPECT(!result[jss::result].isMember(jss::error_code));
+            BEAST_EXPECT(result[jss::result][jss::error_message].isNull());
         }
     }
 

src/test/rpc/TransactionHistory_test.cpp

@@ -7,6 +7,7 @@
 
 #include <xrpl/beast/unit_test/suite.h>
 #include <xrpl/json/json_value.h>
+#include <xrpl/protocol/ErrorCodes.h>
 #include <xrpl/protocol/SField.h>
 #include <xrpl/protocol/jss.h>
 
@@ -30,8 +31,10 @@ class TransactionHistory_test : public beast::unit_test::Suite
         {
             // no params
             auto const result = env.client().invoke("tx_history", {})[jss::result];
-            BEAST_EXPECT(result[jss::error] == "invalidParams");
             BEAST_EXPECT(result[jss::status] == "error");
+            BEAST_EXPECT(result[jss::error] == "invalidParams");
+            BEAST_EXPECT(result[jss::error_code] == RpcInvalidParams);
+            BEAST_EXPECT(result[jss::error_message] == "Invalid parameters.");
         }
 
         {
@@ -39,8 +42,11 @@ class TransactionHistory_test : public beast::unit_test::Suite
             json::Value params{json::ValueType::Object};
             params[jss::start] = 10001;  // limited to <= 10000 for non admin
             auto const result = env.client().invoke("tx_history", params)[jss::result];
-            BEAST_EXPECT(result[jss::error] == "noPermission");
             BEAST_EXPECT(result[jss::status] == "error");
+            BEAST_EXPECT(result[jss::error] == "noPermission");
+            BEAST_EXPECT(result[jss::error_code] == RpcNoPermission);
+            BEAST_EXPECT(
+                result[jss::error_message] == "You don't have permission for this command.");
         }
     }
 
@@ -54,8 +60,10 @@ class TransactionHistory_test : public beast::unit_test::Suite
         json::Value params{json::ValueType::Object};
         params[jss::api_version] = 2;
         auto const result = env.client().invoke("tx_history", params)[jss::result];
-        BEAST_EXPECT(result[jss::error] == "unknownCmd");
         BEAST_EXPECT(result[jss::status] == "error");
+        BEAST_EXPECT(result[jss::error] == "unknownCmd");
+        BEAST_EXPECT(result[jss::error_code] == RpcUnknownCommand);
+        BEAST_EXPECT(result[jss::error_message] == "Unknown method.");
     }
 
     void

src/test/rpc/Transaction_test.cpp

@@ -110,9 +110,10 @@ class Transaction_test : public beast::unit_test::Suite
                 to_string(startLegSeq),
                 to_string(endLegSeq + deltaEndSeq));
 
-            BEAST_EXPECT(
-                result[jss::result][jss::status] == jss::error &&
-                result[jss::result][jss::error] == notFound);
+            BEAST_EXPECT(result[jss::result][jss::status] == jss::error);
+            BEAST_EXPECT(result[jss::result][jss::error] == notFound);
+            BEAST_EXPECT(result[jss::result][jss::error_code] == RpcTxnNotFound);
+            BEAST_EXPECT(result[jss::result][jss::error_message] == "Transaction not found.");
 
             if (deltaEndSeq != 0)
             {
@@ -153,9 +154,10 @@ class Transaction_test : public beast::unit_test::Suite
                 to_string(startLegSeq),
                 to_string(endLegSeq + deltaEndSeq));
 
-            BEAST_EXPECT(
-                result[jss::result][jss::status] == jss::error &&
-                result[jss::result][jss::error] == notFound);
+            BEAST_EXPECT(result[jss::result][jss::status] == jss::error);
+            BEAST_EXPECT(result[jss::result][jss::error] == notFound);
+            BEAST_EXPECT(result[jss::result][jss::error_code] == RpcTxnNotFound);
+            BEAST_EXPECT(result[jss::result][jss::error_message] == "Transaction not found.");
             BEAST_EXPECT(!result[jss::result][jss::searched_all].asBool());
         }
 
@@ -168,9 +170,10 @@ class Transaction_test : public beast::unit_test::Suite
                 to_string(startLegSeq),
                 to_string(endLegSeq));
 
-            BEAST_EXPECT(
-                result[jss::result][jss::status] == jss::error &&
-                result[jss::result][jss::error] == notFound);
+            BEAST_EXPECT(result[jss::result][jss::status] == jss::error);
+            BEAST_EXPECT(result[jss::result][jss::error] == notFound);
+            BEAST_EXPECT(result[jss::result][jss::error_code] == RpcTxnNotFound);
+            BEAST_EXPECT(result[jss::result][jss::error_message] == "Transaction not found.");
 
             BEAST_EXPECT(!result[jss::result][jss::searched_all].asBool());
         }
@@ -184,9 +187,10 @@ class Transaction_test : public beast::unit_test::Suite
                 to_string(startLegSeq),
                 to_string(deletedLedger - 1));
 
-            BEAST_EXPECT(
-                result[jss::result][jss::status] == jss::error &&
-                result[jss::result][jss::error] == notFound);
+            BEAST_EXPECT(result[jss::result][jss::status] == jss::error);
+            BEAST_EXPECT(result[jss::result][jss::error] == notFound);
+            BEAST_EXPECT(result[jss::result][jss::error_code] == RpcTxnNotFound);
+            BEAST_EXPECT(result[jss::result][jss::error_message] == "Transaction not found.");
 
             BEAST_EXPECT(result[jss::result][jss::searched_all].asBool());
         }
@@ -213,9 +217,10 @@ class Transaction_test : public beast::unit_test::Suite
                 to_string(deletedLedger - 1),
                 to_string(startLegSeq));
 
-            BEAST_EXPECT(
-                result[jss::result][jss::status] == jss::error &&
-                result[jss::result][jss::error] == invalid);
+            BEAST_EXPECT(result[jss::result][jss::status] == jss::error);
+            BEAST_EXPECT(result[jss::result][jss::error] == invalid);
+            BEAST_EXPECT(result[jss::result][jss::error_code] == RpcInvalidLgrRange);
+            BEAST_EXPECT(result[jss::result][jss::error_message] == "Ledger range is invalid.");
 
             BEAST_EXPECT(!result[jss::result].isMember(jss::searched_all));
         }
@@ -229,9 +234,10 @@ class Transaction_test : public beast::unit_test::Suite
                 to_string(-1),
                 to_string(deletedLedger - 1));
 
-            BEAST_EXPECT(
-                result[jss::result][jss::status] == jss::error &&
-                result[jss::result][jss::error] == invalid);
+            BEAST_EXPECT(result[jss::result][jss::status] == jss::error);
+            BEAST_EXPECT(result[jss::result][jss::error] == invalid);
+            BEAST_EXPECT(result[jss::result][jss::error_code] == RpcInvalidLgrRange);
+            BEAST_EXPECT(result[jss::result][jss::error_message] == "Ledger range is invalid.");
 
             BEAST_EXPECT(!result[jss::result].isMember(jss::searched_all));
         }
@@ -241,9 +247,10 @@ class Transaction_test : public beast::unit_test::Suite
             auto const result = env.rpc(
                 command, to_string(tx->getTransactionID()), binary, to_string(-20), to_string(-10));
 
-            BEAST_EXPECT(
-                result[jss::result][jss::status] == jss::error &&
-                result[jss::result][jss::error] == invalid);
+            BEAST_EXPECT(result[jss::result][jss::status] == jss::error);
+            BEAST_EXPECT(result[jss::result][jss::error] == invalid);
+            BEAST_EXPECT(result[jss::result][jss::error_code] == RpcInvalidLgrRange);
+            BEAST_EXPECT(result[jss::result][jss::error_message] == "Ledger range is invalid.");
 
             BEAST_EXPECT(!result[jss::result].isMember(jss::searched_all));
         }
@@ -253,9 +260,10 @@ class Transaction_test : public beast::unit_test::Suite
             auto const result =
                 env.rpc(command, to_string(tx->getTransactionID()), binary, to_string(20));
 
-            BEAST_EXPECT(
-                result[jss::result][jss::status] == jss::error &&
-                result[jss::result][jss::error] == invalid);
+            BEAST_EXPECT(result[jss::result][jss::status] == jss::error);
+            BEAST_EXPECT(result[jss::result][jss::error] == invalid);
+            BEAST_EXPECT(result[jss::result][jss::error_code] == RpcInvalidLgrRange);
+            BEAST_EXPECT(result[jss::result][jss::error_message] == "Ledger range is invalid.");
 
             BEAST_EXPECT(!result[jss::result].isMember(jss::searched_all));
         }
@@ -283,9 +291,10 @@ class Transaction_test : public beast::unit_test::Suite
                 to_string(startLegSeq),
                 to_string(startLegSeq + 1001));
 
-            BEAST_EXPECT(
-                result[jss::result][jss::status] == jss::error &&
-                result[jss::result][jss::error] == excessive);
+            BEAST_EXPECT(result[jss::result][jss::status] == jss::error);
+            BEAST_EXPECT(result[jss::result][jss::error] == excessive);
+            BEAST_EXPECT(result[jss::result][jss::error_code] == RpcExcessiveLgrRange);
+            BEAST_EXPECT(result[jss::result][jss::error_message] == "Ledger range exceeds 1000.");
 
             BEAST_EXPECT(!result[jss::result].isMember(jss::searched_all));
         }
@@ -351,9 +360,10 @@ class Transaction_test : public beast::unit_test::Suite
             auto const result = env.rpc(
                 command, ctid, binary, to_string(startLegSeq), to_string(endLegSeq + deltaEndSeq));
 
-            BEAST_EXPECT(
-                result[jss::result][jss::status] == jss::error &&
-                result[jss::result][jss::error] == notFound);
+            BEAST_EXPECT(result[jss::result][jss::status] == jss::error);
+            BEAST_EXPECT(result[jss::result][jss::error] == notFound);
+            BEAST_EXPECT(result[jss::result][jss::error_code] == RpcTxnNotFound);
+            BEAST_EXPECT(result[jss::result][jss::error_message] == "Transaction not found.");
 
             if (deltaEndSeq != 0)
             {
@@ -394,9 +404,10 @@ class Transaction_test : public beast::unit_test::Suite
             auto const result = env.rpc(
                 command, ctid, binary, to_string(startLegSeq), to_string(endLegSeq + deltaEndSeq));
 
-            BEAST_EXPECT(
-                result[jss::result][jss::status] == jss::error &&
-                result[jss::result][jss::error] == notFound);
+            BEAST_EXPECT(result[jss::result][jss::status] == jss::error);
+            BEAST_EXPECT(result[jss::result][jss::error] == notFound);
+            BEAST_EXPECT(result[jss::result][jss::error_code] == RpcTxnNotFound);
+            BEAST_EXPECT(result[jss::result][jss::error_message] == "Transaction not found.");
             BEAST_EXPECT(!result[jss::result][jss::searched_all].asBool());
         }
 
@@ -406,9 +417,10 @@ class Transaction_test : public beast::unit_test::Suite
             auto const result =
                 env.rpc(command, ctid, to_string(startLegSeq), to_string(endLegSeq));
 
-            BEAST_EXPECT(
-                result[jss::result][jss::status] == jss::error &&
-                result[jss::result][jss::error] == notFound);
+            BEAST_EXPECT(result[jss::result][jss::status] == jss::error);
+            BEAST_EXPECT(result[jss::result][jss::error] == notFound);
+            BEAST_EXPECT(result[jss::result][jss::error_code] == RpcTxnNotFound);
+            BEAST_EXPECT(result[jss::result][jss::error_message] == "Transaction not found.");
 
             BEAST_EXPECT(!result[jss::result][jss::searched_all].asBool());
         }
@@ -419,9 +431,10 @@ class Transaction_test : public beast::unit_test::Suite
             auto const result =
                 env.rpc(command, ctid, to_string(startLegSeq), to_string(deletedLedger - 1));
 
-            BEAST_EXPECT(
-                result[jss::result][jss::status] == jss::error &&
-                result[jss::result][jss::error] == notFound);
+            BEAST_EXPECT(result[jss::result][jss::status] == jss::error);
+            BEAST_EXPECT(result[jss::result][jss::error] == notFound);
+            BEAST_EXPECT(result[jss::result][jss::error_code] == RpcTxnNotFound);
+            BEAST_EXPECT(result[jss::result][jss::error_message] == "Transaction not found.");
 
             BEAST_EXPECT(!result[jss::result][jss::searched_all].asBool());
         }
@@ -447,9 +460,10 @@ class Transaction_test : public beast::unit_test::Suite
             auto const result = env.rpc(
                 command, ctid, binary, to_string(deletedLedger - 1), to_string(startLegSeq));
 
-            BEAST_EXPECT(
-                result[jss::result][jss::status] == jss::error &&
-                result[jss::result][jss::error] == invalid);
+            BEAST_EXPECT(result[jss::result][jss::status] == jss::error);
+            BEAST_EXPECT(result[jss::result][jss::error] == invalid);
+            BEAST_EXPECT(result[jss::result][jss::error_code] == RpcInvalidLgrRange);
+            BEAST_EXPECT(result[jss::result][jss::error_message] == "Ledger range is invalid.");
 
             BEAST_EXPECT(!result[jss::result].isMember(jss::searched_all));
         }
@@ -459,9 +473,10 @@ class Transaction_test : public beast::unit_test::Suite
             auto const result =
                 env.rpc(command, ctid, binary, to_string(-1), to_string(deletedLedger - 1));
 
-            BEAST_EXPECT(
-                result[jss::result][jss::status] == jss::error &&
-                result[jss::result][jss::error] == invalid);
+            BEAST_EXPECT(result[jss::result][jss::status] == jss::error);
+            BEAST_EXPECT(result[jss::result][jss::error] == invalid);
+            BEAST_EXPECT(result[jss::result][jss::error_code] == RpcInvalidLgrRange);
+            BEAST_EXPECT(result[jss::result][jss::error_message] == "Ledger range is invalid.");
 
             BEAST_EXPECT(!result[jss::result].isMember(jss::searched_all));
         }
@@ -470,9 +485,10 @@ class Transaction_test : public beast::unit_test::Suite
         {
             auto const result = env.rpc(command, ctid, binary, to_string(-20), to_string(-10));
 
-            BEAST_EXPECT(
-                result[jss::result][jss::status] == jss::error &&
-                result[jss::result][jss::error] == invalid);
+            BEAST_EXPECT(result[jss::result][jss::status] == jss::error);
+            BEAST_EXPECT(result[jss::result][jss::error] == invalid);
+            BEAST_EXPECT(result[jss::result][jss::error_code] == RpcInvalidLgrRange);
+            BEAST_EXPECT(result[jss::result][jss::error_message] == "Ledger range is invalid.");
 
             BEAST_EXPECT(!result[jss::result].isMember(jss::searched_all));
         }
@@ -481,9 +497,10 @@ class Transaction_test : public beast::unit_test::Suite
         {
             auto const result = env.rpc(command, ctid, binary, to_string(20));
 
-            BEAST_EXPECT(
-                result[jss::result][jss::status] == jss::error &&
-                result[jss::result][jss::error] == invalid);
+            BEAST_EXPECT(result[jss::result][jss::status] == jss::error);
+            BEAST_EXPECT(result[jss::result][jss::error] == invalid);
+            BEAST_EXPECT(result[jss::result][jss::error_code] == RpcInvalidLgrRange);
+            BEAST_EXPECT(result[jss::result][jss::error_message] == "Ledger range is invalid.");
 
             BEAST_EXPECT(!result[jss::result].isMember(jss::searched_all));
         }
@@ -507,9 +524,10 @@ class Transaction_test : public beast::unit_test::Suite
             auto const result = env.rpc(
                 command, ctid, binary, to_string(startLegSeq), to_string(startLegSeq + 1001));
 
-            BEAST_EXPECT(
-                result[jss::result][jss::status] == jss::error &&
-                result[jss::result][jss::error] == excessive);
+            BEAST_EXPECT(result[jss::result][jss::status] == jss::error);
+            BEAST_EXPECT(result[jss::result][jss::error] == excessive);
+            BEAST_EXPECT(result[jss::result][jss::error_code] == RpcExcessiveLgrRange);
+            BEAST_EXPECT(result[jss::result][jss::error_message] == "Ledger range exceeds 1000.");
 
             BEAST_EXPECT(!result[jss::result].isMember(jss::searched_all));
         }
@@ -945,6 +963,7 @@ class Transaction_test : public beast::unit_test::Suite
             auto result = signFor(env, tx);
 
             BEAST_EXPECT(result[jss::error] == "invalidParams");
+            BEAST_EXPECT(result[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(result[jss::error_message] == "Missing field 'tx_json.NetworkID'.");
         }
 
@@ -958,6 +977,7 @@ class Transaction_test : public beast::unit_test::Suite
             auto result = signFor(env, tx);
 
             BEAST_EXPECT(result[jss::error] == "invalidParams");
+            BEAST_EXPECT(result[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(result[jss::error_message] == "Invalid field 'tx_json.NetworkID'.");
         }
 
@@ -971,6 +991,7 @@ class Transaction_test : public beast::unit_test::Suite
             auto result = signFor(env, tx);
 
             BEAST_EXPECT(result[jss::error] == "invalidParams");
+            BEAST_EXPECT(result[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(result[jss::error_message] == "Invalid field 'tx_json.NetworkID'.");
         }
 
@@ -985,6 +1006,7 @@ class Transaction_test : public beast::unit_test::Suite
             auto result = signFor(env, tx);
 
             BEAST_EXPECT(result[jss::error] == "invalidParams");
+            BEAST_EXPECT(result[jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(result[jss::error_message] == "Invalid field 'tx_json.NetworkID'.");
         }
 

src/test/rpc/ValidatorInfo_test.cpp

@@ -7,6 +7,7 @@
 
 #include <xrpl/beast/unit_test/suite.h>
 #include <xrpl/config/Constants.h>
+#include <xrpl/protocol/ErrorCodes.h>
 #include <xrpl/protocol/jss.h>
 
 #include <memory>
@@ -27,6 +28,8 @@ public:
         {
             Env env(*this);
             auto const info = env.rpc("validator_info");
+            BEAST_EXPECT(info[jss::result][jss::error] == "invalidParams");
+            BEAST_EXPECT(info[jss::result][jss::error_code] == RpcInvalidParams);
             BEAST_EXPECT(info[jss::result][jss::error_message] == "not a validator");
         }
     }

src/test/server/ServerStatus_test.cpp

@@ -306,33 +306,57 @@ class ServerStatus_test : public beast::unit_test::Suite, public beast::test::En
             // 1 - FAILS with wrong pass
             // NOLINTNEXTLINE(bugprone-unchecked-optional-access)
             jrr = makeAdminRequest(env, proto, *user, *password + "_")[jss::result];
-            BEAST_EXPECT(jrr["error"] == protoWs ? "forbidden" : "noPermission");
-            BEAST_EXPECT(
-                jrr["error_message"] == protoWs ? "Bad credentials."
-                                                : "You don't have permission for this command.");
+            if (protoWs)
+            {
+                BEAST_EXPECT(jrr[jss::error] == "forbidden");
+                BEAST_EXPECT(jrr[jss::error_code] == RpcForbidden);
+                BEAST_EXPECT(jrr[jss::error_message] == "Bad credentials.");
+            }
+            else
+            {
+                BEAST_EXPECT(jrr.isNull());
+            }
 
             // 2 - FAILS with password in an object
             // NOLINTNEXTLINE(bugprone-unchecked-optional-access)
             jrr = makeAdminRequest(env, proto, *user, *password, true)[jss::result];
-            BEAST_EXPECT(jrr["error"] == protoWs ? "forbidden" : "noPermission");
-            BEAST_EXPECT(
-                jrr["error_message"] == protoWs ? "Bad credentials."
-                                                : "You don't have permission for this command.");
+            if (protoWs)
+            {
+                BEAST_EXPECT(jrr[jss::error] == "forbidden");
+                BEAST_EXPECT(jrr[jss::error_code] == RpcForbidden);
+                BEAST_EXPECT(jrr[jss::error_message] == "Bad credentials.");
+            }
+            else
+            {
+                BEAST_EXPECT(jrr.isNull());
+            }
 
             // 3 - FAILS with wrong user
             // NOLINTNEXTLINE(bugprone-unchecked-optional-access)
             jrr = makeAdminRequest(env, proto, *user + "_", *password)[jss::result];
-            BEAST_EXPECT(jrr["error"] == protoWs ? "forbidden" : "noPermission");
-            BEAST_EXPECT(
-                jrr["error_message"] == protoWs ? "Bad credentials."
-                                                : "You don't have permission for this command.");
+            if (protoWs)
+            {
+                BEAST_EXPECT(jrr[jss::error] == "forbidden");
+                BEAST_EXPECT(jrr[jss::error_code] == RpcForbidden);
+                BEAST_EXPECT(jrr[jss::error_message] == "Bad credentials.");
+            }
+            else
+            {
+                BEAST_EXPECT(jrr.isNull());
+            }
 
             // 4 - FAILS no credentials
             jrr = makeAdminRequest(env, proto, "", "")[jss::result];
-            BEAST_EXPECT(jrr["error"] == protoWs ? "forbidden" : "noPermission");
-            BEAST_EXPECT(
-                jrr["error_message"] == protoWs ? "Bad credentials."
-                                                : "You don't have permission for this command.");
+            if (protoWs)
+            {
+                BEAST_EXPECT(jrr[jss::error] == "forbidden");
+                BEAST_EXPECT(jrr[jss::error_code] == RpcForbidden);
+                BEAST_EXPECT(jrr[jss::error_message] == "Bad credentials.");
+            }
+            else
+            {
+                BEAST_EXPECT(jrr.isNull());
+            }
 
             // 5 - SUCCEEDS with proper credentials
             // NOLINTNEXTLINE(bugprone-unchecked-optional-access)
@@ -353,10 +377,16 @@ class ServerStatus_test : public beast::unit_test::Suite, public beast::test::En
         {
             // 1 - FAILS - admin disabled
             jrr = makeAdminRequest(env, proto, "", "")[jss::result];
-            BEAST_EXPECT(jrr["error"] == protoWs ? "forbidden" : "noPermission");
-            BEAST_EXPECT(
-                jrr["error_message"] == protoWs ? "Bad credentials."
-                                                : "You don't have permission for this command.");
+            if (protoWs)
+            {
+                BEAST_EXPECT(jrr[jss::error] == "forbidden");
+                BEAST_EXPECT(jrr[jss::error_code] == RpcForbidden);
+                BEAST_EXPECT(jrr[jss::error_message] == "Bad credentials.");
+            }
+            else
+            {
+                BEAST_EXPECT(jrr.isNull());
+            }
         }
     }
 
@@ -730,7 +760,9 @@ class ServerStatus_test : public beast::unit_test::Suite, public beast::test::En
 
         {  // send invalid json
             auto resp = sendAndParse("NOT JSON");
-            BEAST_EXPECT(resp.isMember(jss::error) && resp[jss::error] == "jsonInvalid");
+            BEAST_EXPECT(resp[jss::error] == "jsonInvalid");
+            BEAST_EXPECT(!resp.isMember(jss::error_code));
+            BEAST_EXPECT(resp[jss::error_message].isNull());
             BEAST_EXPECT(!resp.isMember(jss::status));
         }
 
@@ -739,8 +771,10 @@ class ServerStatus_test : public beast::unit_test::Suite, public beast::test::En
             jv[jss::command] = "foo";
             jv[jss::method] = "bar";
             auto resp = sendAndParse(to_string(jv));
-            BEAST_EXPECT(resp.isMember(jss::error) && resp[jss::error] == "missingCommand");
-            BEAST_EXPECT(resp.isMember(jss::status) && resp[jss::status] == "error");
+            BEAST_EXPECT(resp[jss::status] == "error");
+            BEAST_EXPECT(resp[jss::error] == "missingCommand");
+            BEAST_EXPECT(!resp.isMember(jss::error_code));
+            BEAST_EXPECT(resp[jss::error_message].isNull());
         }
 
         {  // send a ping (not an error)

src/tests/libxrpl/tx/ProposalHelpers.cpp

@@ -48,6 +48,13 @@ TEST(ProposalHelpers, plain_payment_is_valid)
     EXPECT_TRUE(proposal::isValidProposalTxnType(txOfType(ttPAYMENT)));
 }
 
+// No TransactionType at all. STTx construction rejects this first, but the
+// helper takes any STObject, so it must return false rather than throw.
+TEST(ProposalHelpers, typeless_object_is_rejected)
+{
+    EXPECT_FALSE(proposal::isValidProposalTxnType(STObject{sfGeneric}));
+}
+
 // A nested TransactionProposalCreate. In practice STTx construction rejects
 // this earlier (the payload lacks TransactionProposalCreate's own template
 // fields), but the defense here re-checks that guard so the two cannot

src/xrpld/rpc/detail/Handler.cpp

@@ -5,7 +5,10 @@
 #include <xrpld/rpc/Role.h>
 #include <xrpld/rpc/detail/SpecBridge.hpp>
 #include <xrpld/rpc/handlers/Handlers.h>
+#include <xrpld/rpc/handlers/account/AccountChannels.h>
 #include <xrpld/rpc/handlers/account/AccountCurrencies.h>
+#include <xrpld/rpc/handlers/account/AccountInfo.h>
+#include <xrpld/rpc/handlers/account/AccountLines.h>
 #include <xrpld/rpc/handlers/account/AccountNFTs.h>
 #include <xrpld/rpc/handlers/account/AccountOffers.h>
 #include <xrpld/rpc/handlers/ledger/Ledger.h>
@@ -118,7 +121,7 @@ constexpr auto kHandlerArray = std::to_array<Handler>({
     // Request-response methods
     {
         .name = method::kAccountInfo,
-        .valueMethod = Method::of<&byRef<&doAccountInfo>>(),
+        .valueMethod = Method::of<&handle<AccountInfoHandler>>(),
         .role = Role::USER,
         .condition = Condition::NoCondition,
     },
@@ -130,13 +133,13 @@ constexpr auto kHandlerArray = std::to_array<Handler>({
     },
     {
         .name = method::kAccountLines,
-        .valueMethod = Method::of<&byRef<&doAccountLines>>(),
+        .valueMethod = Method::of<&handle<AccountLinesHandler>>(),
         .role = Role::USER,
         .condition = Condition::NoCondition,
     },
     {
         .name = method::kAccountChannels,
-        .valueMethod = Method::of<&byRef<&doAccountChannels>>(),
+        .valueMethod = Method::of<&handle<AccountChannelsHandler>>(),
         .role = Role::USER,
         .condition = Condition::NoCondition,
     },