Skip to main content

Hooks

Hooks provide an extensible event-driven system for automating actions in response to agent commands and events. Hooks are automatically discovered from directories and can be managed via CLI commands, similar to how skills work in OpenClaw.

Getting Oriented

Hooks are small scripts that run when something happens. There are two kinds:
  • Hooks (this page): run inside the Gateway when agent events fire, like /new, /reset, /stop, or lifecycle events.
  • Webhooks: external HTTP webhooks that let other systems trigger work in OpenClaw. See Webhook Hooks or use openclaw webhooks for Gmail helper commands.
Hooks can also be bundled inside plugins; see Plugins. Common uses:
  • Save a memory snapshot when you reset a session
  • Keep an audit trail of commands for troubleshooting or compliance
  • Trigger follow-up automation when a session starts or ends
  • Write files into the agent workspace or call external APIs when events fire
If you can write a small TypeScript function, you can write a hook. Hooks are discovered automatically, and you enable or disable them via the CLI.

Getting Started

Bundled Hooks

OpenClaw ships with five bundled hooks that are automatically discovered:
  • 💾 session-memory: Saves session context to your agent workspace (default ~/.openclaw/workspace/memory/) when you issue /new
  • 📔 session-journal: Writes a reflective LLM journal entry to the lane’s journal/ folder when an opted-in agent issues /new or /reset
  • 📎 bootstrap-extra-files: Injects additional workspace bootstrap files from configured glob/path patterns during agent:bootstrap
  • 📝 command-logger: Logs all command events to ~/.openclaw/logs/commands.log
  • 🚀 boot-md: Runs BOOT.md when the gateway starts (requires internal hooks enabled)
List available hooks:
Enable a hook:
Check hook status:
Get detailed information:

Onboarding

During onboarding (openclaw onboard), you’ll be prompted to enable recommended hooks. The wizard automatically discovers eligible hooks and presents them for selection.

Hook Discovery

Hooks are automatically discovered from three directories (in order of precedence):
  1. Workspace hooks: <workspace>/hooks/ (per-agent, highest precedence)
  2. Managed hooks: ~/.openclaw/hooks/ (user-installed, shared across workspaces)
  3. Bundled hooks: <openclaw>/dist/hooks/bundled/ (shipped with OpenClaw)
Managed hook directories can be either a single hook or a hook pack (package directory). Each hook is a directory containing:

Hook Packs (npm/archives)

Hook packs are standard npm packages that export one or more hooks via openclaw.hooks in package.json. Install them with:
Npm specs are registry-only (package name + optional version/tag). Git/URL/file specs are rejected. Example package.json:
Each entry points to a hook directory containing HOOK.md and handler.ts (or index.ts). Hook packs can ship dependencies; they will be installed under ~/.openclaw/hooks/<id>. Each openclaw.hooks entry must stay inside the package directory after symlink resolution; entries that escape are rejected. Security note: openclaw hooks install installs dependencies with npm install --ignore-scripts (no lifecycle scripts). Keep hook pack dependency trees “pure JS/TS” and avoid packages that rely on postinstall builds.

Hook Structure

HOOK.md Format

The HOOK.md file contains metadata in YAML frontmatter plus Markdown documentation:

Metadata Fields

The metadata.openclaw object supports:
  • emoji: Display emoji for CLI (e.g., "💾")
  • events: Array of events to listen for (e.g., ["command:new", "command:reset"])
  • export: Named export to use (defaults to "default")
  • homepage: Documentation URL
  • requires: Optional requirements
    • bins: Required binaries on PATH (e.g., ["git", "node"])
    • anyBins: At least one of these binaries must be present
    • env: Required environment variables
    • config: Required config paths (e.g., ["workspace.dir"])
    • os: Required platforms (e.g., ["darwin", "linux"])
  • always: Bypass eligibility checks (boolean)
  • install: Installation methods (for bundled hooks: [{"id":"bundled","kind":"bundled"}])

Handler Implementation

The handler.ts file exports a HookHandler function:

Event Context

Each event includes:

Event Types

Command Events

Triggered when agent commands are issued:
  • command: All command events (general listener)
  • command:new: When /new command is issued
  • command:reset: When /reset command is issued
  • command:stop: When /stop command is issued

Agent Events

  • agent:bootstrap: Before workspace bootstrap files are injected (hooks may mutate context.bootstrapFiles)
For lane-aware agents, agent:bootstrap receives context.workspaceLane only when lane resolution is allowed for that bootstrap pass. context.workspaceDir is the effective workspace. Use context.workspaceLane.personaWorkspaceDir when a hook deliberately needs the shared persona workspace. See Workspace Lanes.

Gateway Events

Triggered when the gateway starts:
  • gateway:startup: After channels start and hooks are loaded

Message Events

Triggered when messages are received or sent:
  • message: All message events (general listener)
  • message:received: When an inbound message is received from any channel. Fires early in processing before media understanding. Content may contain raw placeholders like <media:audio> for media attachments that haven’t been processed yet.
  • message:transcribed: When a message has been fully processed, including audio transcription and link understanding. At this point, transcript contains the full transcript text for audio messages. Use this hook when you need access to transcribed audio content.
  • message:preprocessed: Fires for every message after all media + link understanding completes, giving hooks access to the fully enriched body (transcripts, image descriptions, link summaries) before the agent sees it.
  • message:sent: When an outbound message is successfully sent

Message Event Context

Message events include rich context about the message:

Example: Message Logger Hook

Tool Result Hooks (Plugin API)

These hooks are not event-stream listeners; they let plugins synchronously adjust tool results before WednesdayAI persists them.
  • tool_result_persist: transform tool results before they are written to the session transcript. Must be synchronous; return the updated tool result payload or undefined to keep it as-is. See Agent Loop.

Plugin API Hooks (api.on)

Plugin hooks registered via api.on(hookName, handler) intercept the agent pipeline at specific points. Unlike the file-based hook system above, these hooks are registered in code inside a plugin’s register or activate function and are typed end-to-end.

Hook event reference

Runtime and turn identity context

Most plugin API hooks receive optional nested identity objects when WednesdayAI has real identity for that point in the lifecycle:
In the v1 contract, turn.turnId is the same stable string value as runId. The value is minted before message_received on normal inbound dispatch, then carried by value through later hooks. Do not depend on the same object reference being reused across hooks. Important boundaries:
  • conversationId remains the legacy channel conversation id. It is an alias for channelConversationId, never for providerConversationId.
  • providerConversationId is opaque provider/cache identity. It is safe to store as an opaque correlation key, but plugins must not try to reverse or derive it.
  • Early hooks may not have sessionId or sessionKey; WednesdayAI omits those fields rather than fabricating session identity.
  • Public hook contexts do not expose raw identityLinks. Use ctx.runtimeIdentity.canonicalIdentity, ctx.runtimeIdentity.senderIsOwner, or api.runtime.identity.resolveCanonicalIdentity(...) for canonical sender resolution.
Storage append hooks can fire once for the user entry and once for the assistant entry. Both appends share the same turnId, so dedupe with the entry or cursor identity as well:
The typed context lifecycle hooks (context.collect, context.project, context.prune, and storage.afterAppend) use ContextLifecycleContext. That context includes sessionId, sessionKey, runId, storage cursor data when available, sender identity fields, and the same optional runtimeIdentity and turn objects. Use context.collect for context contributions and storage.afterAppend for background capture or extraction queues. model_call_ended carries the completed runId and receives a context whose turn.turnId is aligned to that runId, so usage and provider metadata can be joined back to the same turn. Tool lifecycle hooks also receive foreground identity when it exists. In particular, the production agent tool wrapper passes runtimeIdentity and turn through to before_tool_call, so authorization, audit, and dedupe logic can use the same SDK-owned identity fields before and after a tool executes.

PluginHookAgentContext

The shared context passed to all agent-lifecycle hooks:
trigger and channelId are included in every agent-context hook. Use them to gate logic per channel or trigger type — for example, only apply an output transform for channelId === "telegram" messages triggered by a user.

transform_llm_input

Fires immediately before the messages array is sent to the LLM. Use it to inject additional context, redact sensitive fields, or reorder messages.
Handlers are called sequentially; each handler receives the output of the previous one. Return { messages: [...] } to replace the array, or return nothing to keep the current state. Example — append a confidentiality reminder to the system prompt for every LLM call:

transform_llm_output

Fires after the LLM returns its response, before the reply is delivered to the user. Use it to filter language, redact patterns, or append standard disclaimers.
Handlers are sequential; each receives the prior handler’s output. Example — append a standard disclaimer:

before_prompt_build

Fires after session messages are loaded and the prompt is about to be assembled. Use it to inspect or modify the system prompt, or inject context.
The systemPrompt field on the event is read-only context. To modify it, return { systemPrompt: "..." } in your result. prependContext wrapping: OpenClaw prepends the returned string directly before the user prompt without any automatic XML wrapping. If you want the model to treat the injected text as a system context rather than user-authored input, wrap it yourself:
Omit the wrapper when you want the content to appear as part of the conversation without special XML markup. Example — inject a per-channel system prompt prefix:

Future Events

Planned event types:
  • session:start: When a new session begins
  • session:end: When a session ends
  • agent:error: When an agent encounters an error

Creating Custom Hooks

1. Choose Location

  • Workspace hooks (<workspace>/hooks/): Per-agent, highest precedence
  • Managed hooks (~/.openclaw/hooks/): Shared across workspaces

2. Create Directory Structure

3. Create HOOK.md

4. Create handler.ts

5. Enable and Test

Configuration

Per-Hook Configuration

Hooks can have custom configuration:

Extra Directories

Load hooks from additional directories:

Legacy Config Format (Still Supported)

The old config format still works for backwards compatibility:
Note: module must be a workspace-relative path. Absolute paths and traversal outside the workspace are rejected. Migration: Use the new discovery-based system for new hooks. Legacy handlers are loaded after directory-based hooks.

CLI Commands

List Hooks

Hook Information

Check Eligibility

Enable/Disable

Bundled hook reference

session-memory

Saves session context to memory when you issue /new. Events: command:new Requirements: workspace.dir must be configured Output: <workspace>/memory/YYYY-MM-DD-slug.md (defaults to ~/.openclaw/workspace) What it does:
  1. Uses the pre-reset session entry to locate the correct transcript
  2. Extracts the last 15 lines of conversation
  3. Uses LLM to generate a descriptive filename slug
  4. Saves session metadata to a dated memory file
Example output:
Filename examples:
  • 2026-01-16-143045-vendor-pitch.md
  • 2026-01-16-143045-api-design.md
  • 2026-01-16-143045-journal.md (fallback when slug generation fails or session has no content)
Enable:

bootstrap-extra-files

Injects additional bootstrap files (for example monorepo-local AGENTS.md / TOOLS.md) during agent:bootstrap. Events: agent:bootstrap Requirements: workspace.dir must be configured Output: No files written; bootstrap context is modified in-memory only. Config:
Notes:
  • Paths are resolved relative to workspace.
  • Files must stay inside workspace (realpath-checked).
  • Only recognized bootstrap basenames are loaded.
  • Subagent allowlist is preserved (AGENTS.md and TOOLS.md only).
Enable:

command-logger

Logs all command events to a centralized audit file. Events: command Requirements: None Output: ~/.openclaw/logs/commands.log What it does:
  1. Captures event details (command action, timestamp, session key, sender ID, source)
  2. Appends to log file in JSONL format
  3. Runs silently in the background
Example log entries:
View logs:
Enable:

boot-md

Runs BOOT.md when the gateway starts (after channels start). Internal hooks must be enabled for this to run. Events: gateway:startup Requirements: workspace.dir must be configured What it does:
  1. Reads BOOT.md from your workspace
  2. Runs the instructions via the agent runner
  3. Sends any requested outbound messages via the message tool
Enable:

session-journal

Writes a reflective LLM journal entry when an opted-in agent’s session resets. Events: command:new, command:reset Requirements: opt-in per agent via sessionJournal.enabled: true. workspace.dir is optional — falls back to ~/.openclaw/workspace when not set. Output: <effectiveWorkspaceDir>/journal/YYYY-MM-DD-HHMMss-<slug>.md When workspaceLane is in context (multi-user mode), effectiveWorkspaceDir is the lane-local directory. Otherwise it falls back to the agent’s configured workspace. What it does:
  1. Reads the previous session transcript (JSONL) before it is cleared
  2. Extracts user/assistant turns from the transcript
  3. Calls the LLM to produce a reflective journal entry (patient notes, coaching notes, or a custom prompt)
  4. Writes a dated Markdown file; the filename slug is derived from the first heading in the LLM output
  5. If the LLM call fails or there is no session content, writes a header-only stub so the reset event is still recorded
Configuration: Enable per agent in openclaw.json:
Filename examples:
  • 2026-06-21-143045-vendor-onboarding-session.md
  • 2026-06-21-143045-anxiety-management-techniques.md
  • 2026-06-21-143045-journal.md (fallback when slug generation fails or session has no content)
Limitations: Journal entries are written only when a session explicitly resets via /new or /reset. Sessions that end without a reset command (process exit, connection drop, idle timeout) do not produce a journal entry. Enable:

Best Practices

Keep Handlers Fast

Hooks run during command processing. Keep them lightweight:

Handle Errors Gracefully

Always wrap risky operations:

Filter Events Early

Return early if the event isn’t relevant:

Use Specific Event Keys

Specify exact events in metadata when possible:
Rather than:

Debugging

Enable Hook Logging

The gateway logs hook loading at startup:

Check Discovery

List all discovered hooks:

Check Registration

In your handler, log when it’s called:

Verify Eligibility

Check why a hook isn’t eligible:
Look for missing requirements in the output.

Testing

Gateway Logs

Monitor gateway logs to see hook execution:

Test Hooks Directly

Test your handlers in isolation:

Architecture

Core Components

  • src/hooks/types.ts: Type definitions
  • src/hooks/workspace.ts: Directory scanning and loading
  • src/hooks/frontmatter.ts: HOOK.md metadata parsing
  • src/hooks/config.ts: Eligibility checking
  • src/hooks/hooks-status.ts: Status reporting
  • src/hooks/loader.ts: Dynamic module loader
  • src/cli/hooks-cli.ts: CLI commands
  • src/gateway/server-startup.ts: Loads hooks at gateway start
  • src/auto-reply/reply/commands-core.ts: Triggers command events

Discovery Flow

Event Flow

Troubleshooting

Hook Not Discovered

  1. Check directory structure:
  2. Verify HOOK.md format:
  3. List all discovered hooks:

Hook Not Eligible

Check requirements:
Look for missing:
  • Binaries (check PATH)
  • Environment variables
  • Config values
  • OS compatibility

Hook Not Executing

  1. Verify hook is enabled:
  2. Restart your gateway process so hooks reload.
  3. Check gateway logs for errors:

Handler Errors

Check for TypeScript/import errors:

Migration Guide

From Legacy Config to Discovery

Before:
After:
  1. Create hook directory:
  2. Create HOOK.md:
  3. Update config:
  4. Verify and restart your gateway process:
Benefits of migration:
  • Automatic discovery
  • CLI management
  • Eligibility checking
  • Better documentation
  • Consistent structure

See Also