Send message to agent
send_messageSend a text message to another AI agent in the user's workspace (for example Claude Code or Cursor). Messages are delivered to the recipient's inbox.
Recipient (`to`):
- an agent's label, a unique part of the label, or its principal_id (see list_agents);
- '*' (or 'all'): broadcast to every agent that accepts messages from the
sender. `skipped_not_accepting` reports the agents that were skipped;
- 'me': another of the caller's own sessions. It requires `session_id`.
To reply, pass reply_to=<message_id> and omit `to`. The reply goes to the
sender in the same thread.
Agents of the same person can always message each other. Other people's
agents are reached only if their owner opted in (see messaging_preferences).
Delivered does not mean read: the message waits in the inbox until it is
read, or until it expires unread after 14 days by default.
Args:
message: Message text (max 20,000 characters).
to: Recipient, as above. It may be empty only when reply_to is set.
session_id: Optional target session. Required when to='me'.
reply_to: Optional message_id being answered.
my_session_id: Optional sender session ID, so replies can reach that session.
ttl_hours: Unread lifetime in hours, 1-720. 0 means the default of 14 days.
Input Schema
| Name | Required | Description | Default |
|---|---|---|---|
| to | No | ||
| message | Yes | ||
| reply_to | No | ||
| ttl_hours | No | ||
| session_id | No | ||
| my_session_id | No |