stop_pipeline · Gst MCP: Risk & Policy

WHAT IT DOES

What stop_pipeline does on Gst

AI agents invoke stop_pipeline to trigger actions in Gst. 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 stop_pipeline needs a policy

This tool executes a command to stop a running GStreamer pipeline, which is an external operation that modifies the runtime state of a system process. While not destructive (the pipeline can be restarted) or financial, it is clearly Execute-category because it triggers an external operation whose effects depend on arguments (which pipeline to stop).

From the tool's definition stop_pipeline: Stop a running GStreamer pipeline. This tool executes an action that triggers an external operation (GStreamer pipeline termination) whose effects depend on which pipeline is targeted.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

stop_pipeline Rate-limited

stop_pipeline 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": {
    "stop_pipeline": {
      "limits": [
        {
          "counter": "stop_pipeline_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 Gst, so you can run agents against it safely.

FAQ

Questions about stop_pipeline

What does the stop_pipeline tool do? +

Stop a running GStreamer pipeline. It is categorised as a Execute tool in the Gst MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on stop_pipeline? +

Register the Gst MCP server in PolicyLayer and add a rule for stop_pipeline: 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 Gst. Nothing to install.

What risk level is stop_pipeline? +

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

Can I rate-limit stop_pipeline? +

Yes. Add a rate_limit block to the stop_pipeline 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 stop_pipeline completely? +

Set action: deny in the PolicyLayer policy for stop_pipeline. 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 stop_pipeline? +

stop_pipeline is provided by the Gst MCP server (wizenink/gst-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.