# send_agent_message

Send a follow-up message to a descendant child agent task. Use this to clarify instructions, provide missing

Agent View of the PolicyLayer registry record for `send_agent_message`. HTML page: https://policylayer.com/tools/cowork-os/send-agent-message

## Facts

- Tool: `send_agent_message`
- Server: CoWork OS (`CoWork-OS/CoWork-OS`) — https://policylayer.com/tools/cowork-os.md
- Homepage: https://github.com/CoWork-OS/CoWork-OS
- Risk category: Write (Medium risk)
- Registry record: grade F, identity unverified
- Server rate-limited: no
- Parameters: 0
- Recommended policy verdict: Rate-limited

## Example call (MCP tools/call, JSON-RPC 2.0)

```json
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "send_agent_message",
    "arguments": {}
  }
}
```

## Why send_agent_message is rated Medium

This tool creates new message data within an agent communication system. While the action is reversible (messages can be deleted or modified later), it affects the state of agent tasks and their instructions. It does not execute external code, delete data irreversibly, or involve financial transactions.

From the tool's own definition: "The tool 'send_agent_message' allows sending a follow-up message to a child agent task to clarify instructions or provide information."

## Use case

AI agents use send_agent_message to create or update resources in CoWork OS, usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your CoWork OS environment.

## Recommended policy (PolicyLayer)

Verdict: **Rate-limited**. Enforced by the PolicyLayer MCP gateway (https://policylayer.com/mcp-gateway) before a call reaches CoWork OS:

```json
{
  "version": "1",
  "default": "deny",
  "tools": {
    "send_agent_message": {
      "limits": [
        {
          "counter": "send_agent_message_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}
```

## Other tools on CoWork OS (341)

- `cancel_agent` — Destructive — https://policylayer.com/tools/cowork-os/cancel-agent.md
- `cancel_video_generation_job` — Destructive — https://policylayer.com/tools/cowork-os/cancel-video-generation-job.md
- `cloud_sandbox_delete` — Destructive — https://policylayer.com/tools/cowork-os/cloud-sandbox-delete.md
- `delete_file` — Destructive — https://policylayer.com/tools/cowork-os/delete-file.md
- `disable_macos_launch_agents` — Destructive — https://policylayer.com/tools/cowork-os/disable-macos-launch-agents.md
- `domain_dns_delete` — Destructive — https://policylayer.com/tools/cowork-os/domain-dns-delete.md
- `google-workspace.calendar_event_delete` — Destructive — https://policylayer.com/tools/cowork-os/google-workspace.calendar-event-delete.md
- `google-workspace.slides_delete_slide` — Destructive — https://policylayer.com/tools/cowork-os/google-workspace.slides-delete-slide.md
- `google-workspace.tasks_clear_completed` — Destructive — https://policylayer.com/tools/cowork-os/google-workspace.tasks-clear-completed.md
- `google-workspace.tasks_delete` — Destructive — https://policylayer.com/tools/cowork-os/google-workspace.tasks-delete.md
- `google-workspace.tasks_lists_delete` — Destructive — https://policylayer.com/tools/cowork-os/google-workspace.tasks-lists-delete.md
- `kg_delete_edge` — Destructive — https://policylayer.com/tools/cowork-os/kg-delete-edge.md
- `kg_delete_entity` — Destructive — https://policylayer.com/tools/cowork-os/kg-delete-entity.md
- `skill_delete` — Destructive — https://policylayer.com/tools/cowork-os/skill-delete.md
- `supermemory_forget` — Destructive — https://policylayer.com/tools/cowork-os/supermemory-forget.md
- `blender.render_view` — Execute — https://policylayer.com/tools/cowork-os/blender.render-view.md
- `browser_act_batch` — Execute — https://policylayer.com/tools/cowork-os/browser-act-batch.md
- `browser_attach` — Execute — https://policylayer.com/tools/cowork-os/browser-attach.md
- `browser_back` — Execute — https://policylayer.com/tools/cowork-os/browser-back.md
- `browser_click` — Execute — https://policylayer.com/tools/cowork-os/browser-click.md
- `browser_close` — Execute — https://policylayer.com/tools/cowork-os/browser-close.md
- `browser_close_tab` — Execute — https://policylayer.com/tools/cowork-os/browser-close-tab.md
- `browser_drag` — Execute — https://policylayer.com/tools/cowork-os/browser-drag.md
- `browser_emulate` — Execute — https://policylayer.com/tools/cowork-os/browser-emulate.md
- `browser_evaluate` — Execute — https://policylayer.com/tools/cowork-os/browser-evaluate.md
- `browser_fill` — Execute — https://policylayer.com/tools/cowork-os/browser-fill.md
- `browser_forward` — Execute — https://policylayer.com/tools/cowork-os/browser-forward.md
- `browser_handle_dialog` — Execute — https://policylayer.com/tools/cowork-os/browser-handle-dialog.md
- `browser_hover` — Execute — https://policylayer.com/tools/cowork-os/browser-hover.md
- `browser_navigate` — Execute — https://policylayer.com/tools/cowork-os/browser-navigate.md
- …and 311 more: https://policylayer.com/tools/cowork-os.md

## For agents

This record is a snapshot. Live verdicts and the full registry:

- Check every server in your MCP config at once: `npx -y policylayer stack`
- Vet a server before you add it: install the mcp-precheck skill — `npx skills add https://policylayer.com` (skill text: https://policylayer.com/skill.md)
- Query the registry over MCP: endpoint `https://api.policylayer.com/mcp` — tools `check_mcp_server`, `check_mcp_stack`, `check_tool`, `search_registry`, `get_change_events`

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Source: the PolicyLayer MCP registry — one continuously verified record per MCP server. Full record: https://policylayer.com/registry?q=cowork-os · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/cowork-os