# play_song

Search and play a song on YouTube Music

Agent View of the PolicyLayer registry record for `play_song`. HTML page: https://policylayer.com/tools/4shil-ytm-mcp/play-song

## Facts

- Tool: `play_song`
- Server: Ytm (`4shil/ytm-mcp`) — https://policylayer.com/tools/4shil-ytm-mcp.md
- Homepage: https://github.com/4shil/ytm-mcp
- Risk category: Execute (High risk)
- Registry record: grade B, 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": "play_song",
    "arguments": {}
  }
}
```

## Why play_song is rated High

This tool searches for and initiates playback of a song on an external service (YouTube Music). It executes an external operation whose effects depend on the arguments provided. It is not merely reading data, but actively controlling playback on a platform, placing it in the Execute category.

From the tool's own definition: "'Search and play a song on YouTube Music' — triggers external playback operation on YouTube Music"

## Use case

AI agents invoke play_song to trigger actions in Ytm. What it does depends on the arguments the agent supplies, and its effects often reach beyond the immediate call: builds kicked off, notifications sent, workflows started.

## Recommended policy (PolicyLayer)

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

```json
{
  "version": "1",
  "default": "deny",
  "tools": {
    "play_song": {
      "limits": [
        {
          "counter": "play_song_rate",
          "window": "minute",
          "max": 10,
          "scope": "grant"
        }
      ]
    }
  }
}
```

## Other tools on Ytm (11)

- `playback_control` — Execute — https://policylayer.com/tools/4shil-ytm-mcp/playback-control.md
- `download_history` — Read — https://policylayer.com/tools/4shil-ytm-mcp/download-history.md
- `export_playlist` — Read — https://policylayer.com/tools/4shil-ytm-mcp/export-playlist.md
- `get_current_song` — Read — https://policylayer.com/tools/4shil-ytm-mcp/get-current-song.md
- `get_history` — Read — https://policylayer.com/tools/4shil-ytm-mcp/get-history.md
- `list_downloads` — Read — https://policylayer.com/tools/4shil-ytm-mcp/list-downloads.md
- `list_playlists` — Read — https://policylayer.com/tools/4shil-ytm-mcp/list-playlists.md
- `search_song` — Read — https://policylayer.com/tools/4shil-ytm-mcp/search-song.md
- `add_to_playlist` — Write — https://policylayer.com/tools/4shil-ytm-mcp/add-to-playlist.md
- `create_playlist` — Write — https://policylayer.com/tools/4shil-ytm-mcp/create-playlist.md
- `download_song` — Write — https://policylayer.com/tools/4shil-ytm-mcp/download-song.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`

---

Source: the PolicyLayer MCP registry — one continuously verified record per MCP server. Full record: https://policylayer.com/registry?q=4shil-ytm-mcp · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/4shil-ytm-mcp