diff --git a/examples/hpclient/text-client.js b/examples/hpclient/text-client.js
new file mode 100644
index 00000000..8749e2c1
--- /dev/null
+++ b/examples/hpclient/text-client.js
@@ -0,0 +1,150 @@
+//
+// HotPocket client example code adopted from:
+// https://github.com/codetsunami/hotpocket/blob/master/hp_client.js
+//
+
+const fs = require('fs')
+const ws_api = require('ws');
+const sodium = require('libsodium-wrappers')
+const readline = require('readline')
+
+// sodium has a trigger when it's ready, we will wait and execute from there
+sodium.ready.then(main).catch((e) => { console.log(e) })
+
+
+function main() {
+
+    var keys = sodium.crypto_sign_keypair()
+
+
+    // check for client keys
+    if (!fs.existsSync('.hp_client_keys')) {
+        keys.privateKey = sodium.to_hex(keys.privateKey)
+        keys.publicKey = sodium.to_hex(keys.publicKey)
+        fs.writeFileSync('.hp_client_keys', JSON.stringify(keys))
+    } else {
+        keys = JSON.parse(fs.readFileSync('.hp_client_keys'))
+        keys.privateKey = Uint8Array.from(Buffer.from(keys.privateKey, 'hex'))
+        keys.publicKey = Uint8Array.from(Buffer.from(keys.publicKey, 'hex'))
+    }
+
+
+    var server = 'wss://localhost:8080'
+
+    if (process.argv.length == 3) server = 'wss://localhost:' + process.argv[2]
+
+    if (process.argv.length == 4) server = 'wss://' + process.argv[2] + ':' + process.argv[3]
+
+    var ws = new ws_api(server, {
+        rejectUnauthorized: false
+    })
+
+    /* anatomy of a public challenge
+       {
+       version: '0.1',
+       type: 'public_challenge',
+       challenge: '<hex string>'
+       }
+     */
+
+
+    // if the console ctrl + c's us we should close ws gracefully
+    process.once('SIGINT', function (code) {
+        console.log('SIGINT received...');
+        ws.close()
+    });
+
+    function create_input_container(inp) {
+        let inp_container = {
+            nonce: (new Date()).getTime().toString(),
+            input: Buffer.from(inp).toString('hex'),
+            max_ledger_seqno: 9999999
+        }
+        let inp_container_bytes = JSON.stringify(inp_container);
+        let sig_bytes = sodium.crypto_sign_detached(inp_container_bytes, keys.privateKey);
+
+        let signed_inp_container = {
+            type: "contract_input",
+            content: inp_container_bytes.toString('hex'),
+            sig: Buffer.from(sig_bytes).toString('hex')
+        }
+
+        return JSON.stringify(signed_inp_container);
+    }
+
+    function create_status_request() {
+        let statreq = { type: 'stat' }
+        return JSON.stringify(statreq);
+    }
+
+    function handle_public_challange(m) {
+        let pkhex = 'ed' + Buffer.from(keys.publicKey).toString('hex');
+        console.log('My public key is: ' + pkhex);
+
+        // sign the challenge and send back the response
+        var sigbytes = sodium.crypto_sign_detached(m.challenge, keys.privateKey);
+        var response = {
+            type: 'challenge_resp',
+            challenge: m.challenge,
+            sig: Buffer.from(sigbytes).toString('hex'),
+            pubkey: pkhex
+        }
+
+        ws.send(JSON.stringify(response))
+
+        // start listening for stdin
+        const rl = readline.createInterface({
+            input: process.stdin,
+            output: process.stdout
+        });
+
+        console.log("Ready to accept inputs.")
+
+        // Capture user input from the console.
+        var input_pump = () => {
+            rl.question('', (inp) => {
+
+                let msgtosend = "";
+
+                if (inp == "stat")
+                    msgtosend = create_status_request();
+                else
+                    msgtosend = create_input_container(inp);
+
+                ws.send(msgtosend)
+
+                input_pump()
+            })
+        }
+        input_pump();
+    }
+
+    ws.on('message', (data) => {
+
+        try {
+            m = JSON.parse(data)
+        } catch (e) {
+            console.log("Exception: " + data);
+            return
+        }
+
+        if (m.type == 'public_challenge') {
+            handle_public_challange(m);
+        }
+        else if (m.type == 'contract_output') {
+            console.log(Buffer.from(m.content, 'hex').toString());
+        }
+        else if (m.type == 'request_status_result') {
+            if (m.status != "accepted")
+                console.log("Input status: " + m.status);
+        }
+        else {
+            console.log(m);
+        }
+
+    });
+
+    ws.on('close', () => {
+        console.log('Server disconnected.');
+    });
+}
diff --git a/examples/todo_contract/.gitignore b/examples/todo_contract/.gitignore
new file mode 100644
index 00000000..8d4a6c08
--- /dev/null
+++ b/examples/todo_contract/.gitignore
@@ -0,0 +1,2 @@
+bin
+obj
\ No newline at end of file
diff --git a/examples/todo_contract/DbModel.cs b/examples/todo_contract/DbModel.cs
new file mode 100644
index 00000000..74921604
--- /dev/null
+++ b/examples/todo_contract/DbModel.cs
@@ -0,0 +1,19 @@
+using Microsoft.EntityFrameworkCore;
+
+namespace ToDoContract
+{
+    public class DataContext : DbContext
+    {
+        public DbSet<ToDoEntry> ToDoEntries { get; set; }
+
+        protected override void OnConfiguring(DbContextOptionsBuilder options)
+            => options.UseSqlite("Data Source=state/todo.db");
+    }
+
+    public class ToDoEntry
+    {
+        public int Id { get; set; }
+        public string Content { get; set; }
+        public string CreatedBy { get; set; }
+    }
+}
\ No newline at end of file
diff --git a/examples/todo_contract/HPHelper.cs b/examples/todo_contract/HPHelper.cs
new file mode 100644
index 00000000..b925f4eb
--- /dev/null
+++ b/examples/todo_contract/HPHelper.cs
@@ -0,0 +1,68 @@
+using System;
+using System.IO;
+using System.Text;
+using System.Threading.Tasks;
+using Mono.Unix.Native;
+using Newtonsoft.Json;
+
+namespace HotPocket
+{
+    public static class HotPocketHelper
+    {
+        const int FD_READ_BUFFER_LEN = 1024;
+
+        public static async Task<ContractArgs> GetContractArgsAsync()
+        {
+            using (var s = new StreamReader(Console.OpenStandardInput()))
+            {
+                var input = await s.ReadToEndAsync();
+                var contractArgs = JsonConvert.DeserializeObject<ContractArgs>(input);
+                return contractArgs;
+            }
+        }
+
+        public static string ReadStringFromFD(int fd)
+        {
+            return Encoding.UTF8.GetString(ReadBytesFromFD(fd));
+        }
+
+        public static void WriteStringToFD(int fd, string str)
+        {
+            WriteBytesToFD(fd, Encoding.UTF8.GetBytes(str));
+        }
+
+        public static unsafe byte[] ReadBytesFromFD(int fd)
+        {
+            // Keep reading the fd bytes and fill the memory stream until no more bytes.
+            using (var ms = new MemoryStream())
+            {
+                int readbytes = 0;
+
+                do
+                {
+                    var buffer = new byte[FD_READ_BUFFER_LEN];
+
+                    fixed (byte* p = buffer)
+                    {
+                        IntPtr ptr = (IntPtr)p;
+                        readbytes = (int)Syscall.read(fd, ptr, FD_READ_BUFFER_LEN);
+                    }
+
+                    ms.Write(buffer, 0, readbytes);
+
+                } while (readbytes == FD_READ_BUFFER_LEN);
+
+                return ms.ToArray();
+            }
+        }
+
+        public static unsafe void WriteBytesToFD(int fd, byte[] buffer)
+        {
+            fixed (byte* p = buffer)
+            {
+                IntPtr ptr = (IntPtr)p;
+                Syscall.write(fd, ptr, (ulong)buffer.Length);
+            }
+        }
+    }
+}
\ No newline at end of file
diff --git a/examples/todo_contract/HPModel.cs b/examples/todo_contract/HPModel.cs
new file mode 100644
index 00000000..2a514806
--- /dev/null
+++ b/examples/todo_contract/HPModel.cs
@@ -0,0 +1,64 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using Newtonsoft.Json;
+using Newtonsoft.Json.Linq;
+
+namespace HotPocket
+{
+    public class ContractArgs
+    {
+        [JsonProperty("version")]
+        public string Version { get; set; }
+
+        [JsonProperty("pubkey")]
+        public string PubKey { get; set; }
+
+        [JsonProperty("ts")]
+        public string Timestamp { get; set; }
+
+        [JsonProperty("hpfd")]
+        public IOPipe HotPocketPipe { get; set; }
+
+        [JsonProperty("nplfd")]
+        public IOPipe NplPipe { get; set; }
+
+        [JsonProperty("usrfd")]
+        public Dictionary<string, IOPipe> UserPipes { get; set; }
+
+        [JsonProperty("unl")]
+        public string[] Unl { get; set; }
+    }
+
+    [JsonConverter(typeof(IOPipeJsonConverter))]
+    public class IOPipe
+    {
+        public int ReadFD { get; set; }
+        public int WriteFD { get; set; }
+    }
+
+    public class IOPipeJsonConverter : JsonConverter
+    {
+        public override bool CanConvert(Type objectType)
+        {
+            return objectType == typeof(IOPipe);
+        }
+
+        public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer)
+        {
+            if (reader.TokenType == JsonToken.Null)
+                return null;
+            var array = JArray.Load(reader);
+            var pipe = (existingValue as IOPipe ?? new IOPipe());
+            pipe.ReadFD = (int)array.ElementAtOrDefault(0);
+            pipe.WriteFD = (int)array.ElementAtOrDefault(1);
+            return pipe;
+        }
+
+        public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)
+        {
+            var pipe = (IOPipe)value;
+            serializer.Serialize(writer, new[] { pipe.ReadFD, pipe.WriteFD });
+        }
+    }
+}
\ No newline at end of file
diff --git a/examples/todo_contract/Migrations/20200114133142_InitialCreate.Designer.cs b/examples/todo_contract/Migrations/20200114133142_InitialCreate.Designer.cs
new file mode 100644
index 00000000..f639f5fe
--- /dev/null
+++ b/examples/todo_contract/Migrations/20200114133142_InitialCreate.Designer.cs
@@ -0,0 +1,39 @@
+// <auto-generated />
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Infrastructure;
+using Microsoft.EntityFrameworkCore.Migrations;
+using Microsoft.EntityFrameworkCore.Storage.ValueConversion;
+using ToDoContract;
+
+namespace ToDoContract.Migrations
+{
+    [DbContext(typeof(DataContext))]
+    [Migration("20200114133142_InitialCreate")]
+    partial class InitialCreate
+    {
+        protected override void BuildTargetModel(ModelBuilder modelBuilder)
+        {
+#pragma warning disable 612, 618
+            modelBuilder
+                .HasAnnotation("ProductVersion", "3.1.0");
+
+            modelBuilder.Entity("ToDoContract.ToDoEntry", b =>
+                {
+                    b.Property<int>("Id")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("INTEGER");
+
+                    b.Property<string>("Content")
+                        .HasColumnType("TEXT");
+
+                    b.Property<string>("CreatedBy")
+                        .HasColumnType("TEXT");
+
+                    b.HasKey("Id");
+
+                    b.ToTable("ToDoEntries");
+                });
+#pragma warning restore 612, 618
+        }
+    }
+}
diff --git a/examples/todo_contract/Migrations/20200114133142_InitialCreate.cs b/examples/todo_contract/Migrations/20200114133142_InitialCreate.cs
new file mode 100644
index 00000000..3f32939f
--- /dev/null
+++ b/examples/todo_contract/Migrations/20200114133142_InitialCreate.cs
@@ -0,0 +1,30 @@
+using Microsoft.EntityFrameworkCore.Migrations;
+
+namespace ToDoContract.Migrations
+{
+    public partial class InitialCreate : Migration
+    {
+        protected override void Up(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.CreateTable(
+                name: "ToDoEntries",
+                columns: table => new
+                {
+                    Id = table.Column<int>(nullable: false)
+                        .Annotation("Sqlite:Autoincrement", true),
+                    Content = table.Column<string>(nullable: true),
+                    CreatedBy = table.Column<string>(nullable: true)
+                },
+                constraints: table =>
+                {
+                    table.PrimaryKey("PK_ToDoEntries", x => x.Id);
+                });
+        }
+
+        protected override void Down(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.DropTable(
+                name: "ToDoEntries");
+        }
+    }
+}
diff --git a/examples/todo_contract/Migrations/DataContextModelSnapshot.cs b/examples/todo_contract/Migrations/DataContextModelSnapshot.cs
new file mode 100644
index 00000000..09f9130f
--- /dev/null
+++ b/examples/todo_contract/Migrations/DataContextModelSnapshot.cs
@@ -0,0 +1,37 @@
+// <auto-generated />
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Infrastructure;
+using Microsoft.EntityFrameworkCore.Storage.ValueConversion;
+using ToDoContract;
+
+namespace ToDoContract.Migrations
+{
+    [DbContext(typeof(DataContext))]
+    partial class DataContextModelSnapshot : ModelSnapshot
+    {
+        protected override void BuildModel(ModelBuilder modelBuilder)
+        {
+#pragma warning disable 612, 618
+            modelBuilder
+                .HasAnnotation("ProductVersion", "3.1.0");
+
+            modelBuilder.Entity("ToDoContract.ToDoEntry", b =>
+                {
+                    b.Property<int>("Id")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("INTEGER");
+
+                    b.Property<string>("Content")
+                        .HasColumnType("TEXT");
+
+                    b.Property<string>("CreatedBy")
+                        .HasColumnType("TEXT");
+
+                    b.HasKey("Id");
+
+                    b.ToTable("ToDoEntries");
+                });
+#pragma warning restore 612, 618
+        }
+    }
+}
diff --git a/examples/todo_contract/Program.cs b/examples/todo_contract/Program.cs
new file mode 100644
index 00000000..d2042089
--- /dev/null
+++ b/examples/todo_contract/Program.cs
@@ -0,0 +1,136 @@
+using System;
+using System.Threading.Tasks;
+using Microsoft.EntityFrameworkCore;
+using Newtonsoft.Json;
+using HotPocket;
+using System.Linq;
+
+namespace ToDoContract
+{
+    /* 
+     * This is a simple multi-user ToDo list contract which uses sqlite database as storage.
+     * In order to run this .Net Core should be installed on the system. If using docker,
+     * mcr.microsoft.com/dotnet/core/sdk:3.1 docker image must be used.
+     * 
+     * Produce deployable output with: dotnet publish -c Release
+     *
+     * User inputs can be submitted in the following format.
+     * Insert a new ToDo record:            add <title>
+     * Retrieve all records owned by user:  get all
+     * Retrieve record by ID:               get <id>
+     * Delete all records owned by user:    delete all
+     * Delete record by ID:                 delete <id>
+     */
+    public class Program
+    {
+        static async Task Main(string[] args)
+        {
+            Console.WriteLine("Starting .Net ToDo contract");
+
+            using (var dataContext = new DataContext())
+            {
+                dataContext.Database.Migrate();
+            }
+
+            ContractArgs contractArgs = await HotPocketHelper.GetContractArgsAsync();
+
+            foreach (var user in contractArgs.UserPipes)
+            {
+                var pubkey = user.Key;
+                var pipe = user.Value;
+
+                var input = HotPocketHelper.ReadStringFromFD(pipe.ReadFD);
+                if (string.IsNullOrEmpty(input))
+                    continue;
+
+                var output = await HandleUserInputAsync(pubkey, input);
+                HotPocketHelper.WriteStringToFD(pipe.WriteFD, output);
+            }
+        }
+
+        static async Task<string> HandleUserInputAsync(string userId, string input)
+        {
+            var parts = input.Trim().Split(' ', 2);
+            if (parts.Length < 2)
+                return "Invalid input format";
+
+            var command = parts[0].ToLower();
+            var param = parts[1];
+
+            using (var dataContext = new DataContext())
+            {
+                if (command == "add") // add new record.
+                {
+                    var entry = new ToDoEntry
+                    {
+                        Content = param,
+                        CreatedBy = userId
+                    };
+                    dataContext.ToDoEntries.Add(entry);
+
+                    await dataContext.SaveChangesAsync();
+
+                    return "Added entry with id " + entry.Id;
+                }
+                else if (command == "get" || command == "delete")
+                {
+                    if (param == "all") // get/delete all records.
+                    {
+                        // Get all entries belonging to this user.
+                        var entries = await dataContext.ToDoEntries.Where(e => e.CreatedBy == userId).OrderBy(e => e.Id).ToListAsync();
+
+                        if (command == "get")
+                        {
+                            return JsonConvert.SerializeObject(entries.Select(e => $"ID-{e.Id}: {e.Content}"));
+                        }
+                        else
+                        {
+                            // Delete all records for this user.
+                            dataContext.RemoveRange(entries);
+                            await dataContext.SaveChangesAsync();
+                            return $"{entries.Count} record(s) deleted";
+
+                        }
+                    }
+                    else // get/delete by ID.
+                    {
+                        int id = 0;
+                        if (int.TryParse(param, out id))
+                        {
+                            var entry = await dataContext.ToDoEntries.FirstOrDefaultAsync(e => e.Id == id);
+                            if (entry == null)
+                            {
+                                return $"Record id {id} does not exist";
+                            }
+                            else if (entry.CreatedBy != userId)
+                            {
+                                return $"You do not have permission for record id {id}";
+                            }
+                            else
+                            {
+                                if (command == "get")
+                                {
+                                    return entry.Content;
+                                }
+                                else
+                                {
+                                    dataContext.Remove(entry);
+                                    await dataContext.SaveChangesAsync();
+                                    return $"Record id {id} deleted";
+                                }
+                            }
+                        }
+                        else
+                        {
+                            return "Invalid record id";
+                        }
+                    }
+                }
+                else
+                {
+                    return "Invalid command";
+                }
+            }
+        }
+    }
+}
diff --git a/examples/todo_contract/ToDoContract.csproj b/examples/todo_contract/ToDoContract.csproj
new file mode 100644
index 00000000..955a561e
--- /dev/null
+++ b/examples/todo_contract/ToDoContract.csproj
@@ -0,0 +1,19 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>netcoreapp3.1</TargetFramework>
+    <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Microsoft.EntityFrameworkCore.Design" Version="3.1.0">
+      <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
+      <PrivateAssets>all</PrivateAssets>
+    </PackageReference>
+    <PackageReference Include="Microsoft.EntityFrameworkCore.Sqlite" Version="3.1.0" />
+    <PackageReference Include="Mono.Posix.NETStandard" Version="1.0.0" />
+    <PackageReference Include="Newtonsoft.Json" Version="12.0.3" />
+  </ItemGroup>
+
+</Project>
diff --git a/src/jsonschema/usrmsg_helpers.cpp b/src/jsonschema/usrmsg_helpers.cpp
index ef1403a5..42273f09 100644
--- a/src/jsonschema/usrmsg_helpers.cpp
+++ b/src/jsonschema/usrmsg_helpers.cpp
@@ -146,9 +146,9 @@ void create_request_status_result(std::string &msg, std::string_view status, std
         .append(reason)
         .append(SEP_COMMA)
         .append(FLD_ORIGIN)
-        .append(":{")
+        .append("\":{\"")
         .append(FLD_TYPE)
-        .append(SEP_COMMA)
+        .append(SEP_COLON)
         .append(origin_type)
         .append("\"")
         .append(origin_extra_data)
diff --git a/test/local-cluster/cluster-create.sh b/test/local-cluster/cluster-create.sh
index 19839dbf..dd5df1b3 100755
--- a/test/local-cluster/cluster-create.sh
+++ b/test/local-cluster/cluster-create.sh
@@ -67,6 +67,7 @@ do
     mkdir ./node$n/bin
     cp ../../../examples/echo_contract/contract.js ./node$n/bin/contract.js
     cp ../bin/appbill ./node$n/bin/
+    # cp -r ../../../examples/todo_contract/bin/Release/netcoreapp3.1/publish/* ./node$n/bin/
 done
 
 # Function to generate JSON array string while skiping a given index.