# hooks-emit-prereq

Before emitting a transaction using [emit](https://xrpl-hooks.readme.io/v2.0/reference/emit) Hook API, a hook must set a maximal count of transactions it plans to emit, by calling [etxn_reserve](https://xrpl-hooks.readme.io/v2.0/reference/etxn_reserve).

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