# hooks-detail-prereq

Hook API [etxn_details](https://xrpl-hooks.readme.io/v2.0/reference/etxn_details) serializes emit details, based on (i.a.) the number of reserved transactions, so a call to it must be preceded by a call to [etxn_reserve](https://xrpl-hooks.readme.io/v2.0/reference/etxn_reserve).

[Read more](https://xrpl-hooks.readme.io/v2.0/docs/emitted-transactions)