SendMessage tool description
27 model strings share this prompt, byte for byte.
This renders the markdown inside the description, so it isn't quite the description itself. The raw view and the plain text are the bytes as they were sent.
SendMessage
Send a message to another agent.
{"to": "researcher", "summary": "assign task 1", "message": "start on task #1"}
| to | |
|---|---|
| "researcher" | Teammate by name |
| "main" | The main conversation (background subagents only) |
Your plain text output is NOT visible to other agents — to communicate, you MUST call this tool. Messages from teammates are delivered automatically; you don't check an inbox. Refer to agents by name — names keep working after an agent completes (a send resumes it from its transcript). Use the raw agentId (format a...-...) from its spawn result only when the agent has no name, or when a newer agent took the name (latest wins). When relaying, don't quote the original — it's already rendered to the user.