Feature Request

Add a message:received hook event that fires before the agent processes an incoming message. This would enable pre-processing workflows like:

• Fetching thread context for Slack/Discord before the agent responds
• Enriching messages with external data
• Filtering or transforming messages before agent processing
• Adding metadata or context injection

Use Case

When an agent is tagged in a Slack thread, OpenClaw currently only provides the root message + current message. The agent cannot see the thread history, leading to context-blind responses.

With a message:received hook, we could:

1. Detect if the message is in a thread
2. Fetch full thread history via Slack API
3. Inject that context before the agent processes

Proposed API

const handler: HookHandler = async (event) => {
  if (event.type !== 'message' || event.action !== 'received') return;
  
  const { channel, threadId, channelId } = event.context;
  
  if (channel === 'slack' && threadId) {
    // Fetch thread replies
    const replies = await fetchSlackThreadReplies(channelId, threadId);
    // Inject into context
    event.context.threadContext = replies;
  }
};

Current Workaround

Manual script call in agent instructions (AGENTS.md):

scripts/slack_thread_replies.sh <channel_id> <thread_ts> 30

This is error-prone as it relies on the agent remembering to call it.

Related

• Docs mention message:received as a planned event: https://docs.openclaw.ai/automation/hooks
• Related bug: message(action=read, threadId=X) returns channel messages instead of thread replies #12866 (threadId parameter not working in message read action)

Environment

• OpenClaw version: 2026.2.6-3