process_stop · Promethean OS MCP: Risk & Policy

WHAT IT DOES

What process_stop does on Promethean OS MCP

AI agents invoke process_stop to trigger actions in Promethean OS MCP. 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 process_stop needs a policy

Stopping processes is an Execute action: it triggers an external operation with effects determined by the arguments provided. While not immediately destructive, a running task might be critical infrastructure, a user session, or data-processing pipeline whose termination could cause data loss, service disruption, or user impact.

From the tool's definition Tool description states 'Stop a running task via id, pid, or name' - this triggers an external operation (process termination) whose effects depend on which process is targeted.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

process_stop Rate-limited

process_stop 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": {
    "process_stop": {
      "limits": [
        {
          "counter": "process_stop_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 Promethean OS MCP, so you can run agents against it safely.

FAQ

Questions about process_stop

What does the process_stop tool do? +

Stop a running task via id, pid, or name and return trailing output. It is categorised as a Execute tool in the Promethean OS MCP MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on process_stop? +

Register the Promethean OS MCP server in PolicyLayer and add a rule for process_stop: 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 Promethean OS MCP. Nothing to install.

What risk level is process_stop? +

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

Can I rate-limit process_stop? +

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

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

process_stop is provided by the Promethean OS MCP server (octave-commons/mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.