play_movie · MCP Media Server MCP: Risk & Policy

WHAT IT DOES

What play_movie does on MCP Media Server

AI agents invoke play_movie to trigger actions in MCP Media Server. 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.

WHY IT NEEDS A POLICY

Why play_movie needs a policy

This tool executes an external process (MPV media player) to perform media playback, which qualifies as Execute rather than Read or Write. While media playback itself is relatively benign, the tool's ability to launch processes and control system resources warrants medium severity. It is not Destructive (no data deletion), Financial (no money involved), or Write (not creating/modifying persistent data).

From the tool's definition Tool description states it "Play[s] a specific movie file using MPV" and will "stop" any currently playing media. The action of launching an external process (MPV media player) with IPC control constitutes code/process execution.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

play_movie Rate-limited

play_movie stays usable, but rate-capped — a runaway agent can't fire it dozens of times a minute. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "play_movie": {
      "limits": [
        {
          "counter": "play_movie_rate",
          "window": "minute",
          "max": 10,
          "scope": "grant"
        }
      ]
    }
  }
}

RATE-LIMIT THIS TOOL →

Instant setup, no code required.

PolicyLayer is an MCP gateway: every tool call is checked against your rule before it reaches MCP Media Server, so you can run agents against it safely.

FAQ

Questions about play_movie

What does the play_movie tool do? +

Play a specific movie file using MPV with IPC control. Supports fuzzy matching by name and optional loop parameter. If another movie is playing, it will be stopped first. It is categorised as a Execute tool in the MCP Media Server MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on play_movie? +

Register the MCP Media Server MCP server in PolicyLayer and add a rule for play_movie: allow, deny, rate-limit, or require approval. Point your MCP client at the PolicyLayer proxy URL and the rule is enforced on every call, before it reaches MCP Media Server. Nothing to install.

What risk level is play_movie? +

play_movie is a Execute tool with high risk. Execute tools should be rate-limited and have argument validation enabled.

Can I rate-limit play_movie? +

Yes. Add a rate_limit block to the play_movie rule in your PolicyLayer policy. For example, setting max: 10 and window: 60 limits the tool to 10 calls per minute. Rate limits are tracked per agent session and reset automatically.

How do I block play_movie completely? +

Set action: deny in the PolicyLayer policy for play_movie. The AI agent will receive a policy violation error and cannot call the tool. You can also include a reason field to explain why the tool is blocked.

What MCP server provides play_movie? +

play_movie is provided by the MCP Media Server MCP server (neal3000/mcp_media_server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.