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

# Hooks

Hooks are small scripts that run when something happens inside the Gateway. They can be discovered from directories and inspected with `fluffbuzz hooks`. The Gateway loads internal hooks only after you enable hooks or configure at least one hook entry, hook pack, legacy handler, or extra hook directory.

There are two kinds of hooks in FluffBuzz:

* **Internal hooks** (this page): run inside the Gateway when agent events fire, like `/new`, `/reset`, `/stop`, or lifecycle events.
* **Webhooks**: external HTTP endpoints that let other systems trigger work in FluffBuzz. See [Webhooks](/automation/cron-jobs#webhooks).

Hooks can also be bundled inside plugins. `fluffbuzz hooks list` shows both standalone hooks and plugin-managed hooks.

## Quick start

```bash theme={"theme":{"light":"min-light","dark":"min-dark"}}
# List available hooks
fluffbuzz hooks list

# Enable a hook
fluffbuzz hooks enable session-memory

# Check hook status
fluffbuzz hooks check

# Get detailed information
fluffbuzz hooks info session-memory
```

## Event types

| Event                    | When it fires                                    |
| ------------------------ | ------------------------------------------------ |
| `command:new`            | `/new` command issued                            |
| `command:reset`          | `/reset` command issued                          |
| `command:stop`           | `/stop` command issued                           |
| `command`                | Any command event (general listener)             |
| `session:compact:before` | Before compaction summarizes history             |
| `session:compact:after`  | After compaction completes                       |
| `session:patch`          | When session properties are modified             |
| `agent:bootstrap`        | Before workspace bootstrap files are injected    |
| `gateway:startup`        | After channels start and hooks are loaded        |
| `message:received`       | Inbound message from any channel                 |
| `message:transcribed`    | After audio transcription completes              |
| `message:preprocessed`   | After all media and link understanding completes |
| `message:sent`           | Outbound message delivered                       |

## Writing hooks

### Hook structure

Each hook is a directory containing two files:

```
my-hook/
├── HOOK.md          # Metadata + documentation
└── handler.ts       # Handler implementation
```

### HOOK.md format

```markdown theme={"theme":{"light":"min-light","dark":"min-dark"}}
---
name: my-hook
description: "Short description of what this hook does"
metadata:
  { "fluffbuzz": { "emoji": "🔗", "events": ["command:new"], "requires": { "bins": ["node"] } } }
---

# My Hook

Detailed documentation goes here.
```

**Metadata fields** (`metadata.fluffbuzz`):

| Field      | Description                                          |
| ---------- | ---------------------------------------------------- |
| `emoji`    | Display emoji for CLI                                |
| `events`   | Array of events to listen for                        |
| `export`   | Named export to use (defaults to `"default"`)        |
| `os`       | Required platforms (e.g., `["darwin", "linux"]`)     |
| `requires` | Required `bins`, `anyBins`, `env`, or `config` paths |
| `always`   | Bypass eligibility checks (boolean)                  |
| `install`  | Installation methods                                 |

### Handler implementation

```typescript theme={"theme":{"light":"min-light","dark":"min-dark"}}
const handler = async (event) => {
  if (event.type !== "command" || event.action !== "new") {
    return;
  }

  console.log(`[my-hook] New command triggered`);
  // Your logic here

  // Optionally send message to user
  event.messages.push("Hook executed!");
};

export default handler;
```

Each event includes: `type`, `action`, `sessionKey`, `timestamp`, `messages` (push to send to user), and `context` (event-specific data).

### Event context highlights

**Command events** (`command:new`, `command:reset`): `context.sessionEntry`, `context.previousSessionEntry`, `context.commandSource`, `context.workspaceDir`, `context.cfg`.

**Message events** (`message:received`): `context.from`, `context.content`, `context.channelId`, `context.metadata` (provider-specific data including `senderId`, `senderName`, `guildId`).

**Message events** (`message:sent`): `context.to`, `context.content`, `context.success`, `context.channelId`.

**Message events** (`message:transcribed`): `context.transcript`, `context.from`, `context.channelId`, `context.mediaPath`.

**Message events** (`message:preprocessed`): `context.bodyForAgent` (final enriched body), `context.from`, `context.channelId`.

**Bootstrap events** (`agent:bootstrap`): `context.bootstrapFiles` (mutable array), `context.agentId`.

**Session patch events** (`session:patch`): `context.sessionEntry`, `context.patch` (only changed fields), `context.cfg`. Only privileged clients can trigger patch events.

**Compaction events**: `session:compact:before` includes `messageCount`, `tokenCount`. `session:compact:after` adds `compactedCount`, `summaryLength`, `tokensBefore`, `tokensAfter`.

## Hook discovery

Hooks are discovered from these directories, in order of increasing override precedence:

1. **Bundled hooks**: shipped with FluffBuzz
2. **Plugin hooks**: hooks bundled inside installed plugins
3. **Managed hooks**: `~/.fluffbuzz/hooks/` (user-installed, shared across workspaces). Extra directories from `hooks.internal.load.extraDirs` share this precedence.
4. **Workspace hooks**: `<workspace>/hooks/` (per-agent, disabled by default until explicitly enabled)

Workspace hooks can add new hook names but cannot override bundled, managed, or plugin-provided hooks with the same name.

The Gateway skips internal hook discovery on startup until internal hooks are configured. Enable a bundled or managed hook with `fluffbuzz hooks enable <name>`, install a hook pack, or set `hooks.internal.enabled=true` to opt in. When you enable one named hook, the Gateway loads only that hook's handler; `hooks.internal.enabled=true`, extra hook directories, and legacy handlers opt into broad discovery.

### Hook packs

Hook packs are npm packages that export hooks via `fluffbuzz.hooks` in `package.json`. Install with:

```bash theme={"theme":{"light":"min-light","dark":"min-dark"}}
fluffbuzz plugins install <path-or-spec>
```

Npm specs are registry-only (package name + optional exact version or dist-tag). Git/URL/file specs and semver ranges are rejected.

## Bundled hooks

| Hook                  | Events                         | What it does                                          |
| --------------------- | ------------------------------ | ----------------------------------------------------- |
| session-memory        | `command:new`, `command:reset` | Saves session context to `<workspace>/memory/`        |
| bootstrap-extra-files | `agent:bootstrap`              | Injects additional bootstrap files from glob patterns |
| command-logger        | `command`                      | Logs all commands to `~/.fluffbuzz/logs/commands.log` |
| boot-md               | `gateway:startup`              | Runs `BOOT.md` when the gateway starts                |

Enable any bundled hook:

```bash theme={"theme":{"light":"min-light","dark":"min-dark"}}
fluffbuzz hooks enable <hook-name>
```

<a id="session-memory" />

### session-memory details

Extracts the last 15 user/assistant messages, generates a descriptive filename slug via LLM, and saves to `<workspace>/memory/YYYY-MM-DD-slug.md`. Requires `workspace.dir` to be configured.

<a id="bootstrap-extra-files" />

### bootstrap-extra-files config

```json theme={"theme":{"light":"min-light","dark":"min-dark"}}
{
  "hooks": {
    "internal": {
      "entries": {
        "bootstrap-extra-files": {
          "enabled": true,
          "paths": ["packages/*/AGENTS.md", "packages/*/TOOLS.md"]
        }
      }
    }
  }
}
```

Paths resolve relative to workspace. Only recognized bootstrap basenames are loaded (`AGENTS.md`, `SOUL.md`, `TOOLS.md`, `IDENTITY.md`, `USER.md`, `HEARTBEAT.md`, `BOOTSTRAP.md`, `MEMORY.md`).

<a id="command-logger" />

### command-logger details

Logs every slash command to `~/.fluffbuzz/logs/commands.log`.

<a id="boot-md" />

### boot-md details

Runs `BOOT.md` from the active workspace when the gateway starts.

## Plugin hooks

Plugins can register hooks through the Plugin SDK for deeper integration: intercepting tool calls, modifying prompts, controlling message flow, and more. The Plugin SDK exposes 28 hooks covering model resolution, agent lifecycle, message flow, tool execution, subagent coordination, and gateway lifecycle.

For the complete plugin hook reference including `before_tool_call`, `before_agent_reply`, `before_install`, and all other plugin hooks, see [Plugin Architecture](/plugins/architecture#provider-runtime-hooks).

## Configuration

```json theme={"theme":{"light":"min-light","dark":"min-dark"}}
{
  "hooks": {
    "internal": {
      "enabled": true,
      "entries": {
        "session-memory": { "enabled": true },
        "command-logger": { "enabled": false }
      }
    }
  }
}
```

Per-hook environment variables:

```json theme={"theme":{"light":"min-light","dark":"min-dark"}}
{
  "hooks": {
    "internal": {
      "entries": {
        "my-hook": {
          "enabled": true,
          "env": { "MY_CUSTOM_VAR": "value" }
        }
      }
    }
  }
}
```

Extra hook directories:

```json theme={"theme":{"light":"min-light","dark":"min-dark"}}
{
  "hooks": {
    "internal": {
      "load": {
        "extraDirs": ["/path/to/more/hooks"]
      }
    }
  }
}
```

<Note>
  The legacy `hooks.internal.handlers` array config format is still supported for backwards compatibility, but new hooks should use the discovery-based system.
</Note>

## CLI reference

```bash theme={"theme":{"light":"min-light","dark":"min-dark"}}
# List all hooks (add --eligible, --verbose, or --json)
fluffbuzz hooks list

# Show detailed info about a hook
fluffbuzz hooks info <hook-name>

# Show eligibility summary
fluffbuzz hooks check

# Enable/disable
fluffbuzz hooks enable <hook-name>
fluffbuzz hooks disable <hook-name>
```

## Best practices

* **Keep handlers fast.** Hooks run during command processing. Fire-and-forget heavy work with `void processInBackground(event)`.
* **Handle errors gracefully.** Wrap risky operations in try/catch; do not throw so other handlers can run.
* **Filter events early.** Return immediately if the event type/action is not relevant.
* **Use specific event keys.** Prefer `"events": ["command:new"]` over `"events": ["command"]` to reduce overhead.

## Troubleshooting

### Hook not discovered

```bash theme={"theme":{"light":"min-light","dark":"min-dark"}}
# Verify directory structure
ls -la ~/.fluffbuzz/hooks/my-hook/
# Should show: HOOK.md, handler.ts

# List all discovered hooks
fluffbuzz hooks list
```

### Hook not eligible

```bash theme={"theme":{"light":"min-light","dark":"min-dark"}}
fluffbuzz hooks info my-hook
```

Check for missing binaries (PATH), environment variables, config values, or OS compatibility.

### Hook not executing

1. Verify the hook is enabled: `fluffbuzz hooks list`
2. Restart your gateway process so hooks reload.
3. Check gateway logs: `./scripts/flufflog.sh | grep hook`

## Related

* [CLI Reference: hooks](/cli/hooks)
* [Webhooks](/automation/cron-jobs#webhooks)
* [Plugin Architecture](/plugins/architecture#provider-runtime-hooks) — full plugin hook reference
* [Configuration](/gateway/configuration-reference#hooks)