# Tool Description: SendMessageTool

> Agent teams version of SendMessageTool.

- Skill: `lord1egypt/tool-description-sendmessagetool-2` (Agent Skill)
- Install (CLI): `npx skillmds@latest add lord1egypt/tool-description-sendmessagetool-2`
- Raw SKILL.md: https://api.skillmd.com/api/skills/lord1egypt/tool-description-sendmessagetool-2/raw
- Safety review: pending (external: skill-scanner FAIL, skillspector PASS)
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: AI & ML
- License: BSD-3-Clause license
- Author: Lord1Egypt (https://skillmd.com/u/lord1egypt)
- Updated: 2026-09-21
- Page: https://skillmd.com/skills/lord1egypt/tool-description-sendmessagetool-2

---


# SendMessage

Send a message to another agent.

```json
{"to": "researcher", "summary": "assign task 1", "message": "start on task #1"}
```

| `to` | |
|---|---|
| `"researcher"` | Teammate by name |${""}

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 active teammates by name; to resume a completed background agent, use the `agentId` (format `a...-...`) from its spawn result. When relaying, don't quote the original — it's already rendered to the user.${""}

## Protocol responses (legacy)

If you receive a JSON message with `type: "shutdown_request"` or `type: "plan_approval_request"`, respond with the matching `_response` type — echo the `request_id`, set `approve` true/false:

```json
{"to": "team-lead", "message": {"type": "shutdown_response", "request_id": "...", "approve": true}}
{"to": "researcher", "message": {"type": "plan_approval_response", "request_id": "...", "approve": false, "feedback": "add error handling"}}
```

Approving shutdown terminates your process. Rejecting plan sends the teammate back to revise. Don't originate `shutdown_request` unless asked. Don't send structured JSON status messages — use TaskUpdate.