> ## Documentation Index
> Fetch the complete documentation index at: https://docs.rkat.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Hooks Reference

> Low-level hook surface reference: hook points, capabilities, execution modes, and payload fields.

Use this page when you need exact hook vocabulary and structure rather than a procedural walkthrough.

## Core enums

| Type                | Values                                                                                                                                 |
| ------------------- | -------------------------------------------------------------------------------------------------------------------------------------- |
| `HookPoint`         | `RunStarted`, `PreLlmRequest`, `PreToolExecution`, `TurnBoundary`, `PostLlmResponse`, `PostToolExecution`, `RunCompleted`, `RunFailed` |
| `HookCapability`    | `Observe`, `Guardrail`, `Rewrite` (retired compatibility label; no patch authority)                                                    |
| `HookExecutionMode` | `Foreground`, `Background`                                                                                                             |
| `HookFailurePolicy` | `FailOpen`, `FailClosed`                                                                                                               |

## Runtime families

* in-process
* command
* HTTP

## Payload highlights

* `HookInvocation`
* `HookToolResult`
* `HookDecision`

## See also

* [Hooks guide](/guides/hooks)
* [Examples: Hooks](/examples/hooks)