stop_process · Persistent Shell MCP: Risk & Policy

WHAT IT DOES

What stop_process does on Persistent Shell MCP

AI agents invoke stop_process to trigger actions in Persistent Shell 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 stop_process needs a policy

This tool triggers an external operation (process termination) whose effects depend on which process is currently running in the exec window. While not destructive in the sense of deleting data, it interrupts and terminates active operations, which qualifies as Execute rather than Read or Write.

From the tool's definition Tool stops a running process by sending Ctrl+C signal. The server description explicitly states it 'Enables AI assistants to execute shell commands and manage long-running processes.' The stop_process tool directly controls process execution state, which is a…

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

stop_process Rate-limited

stop_process 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_process": {
      "limits": [
        {
          "counter": "stop_process_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 Persistent Shell MCP, so you can run agents against it safely.

FAQ

Questions about stop_process

What does the stop_process tool do? +

Stop the currently running process in the exec window (sends Ctrl+C). It is categorised as a Execute tool in the Persistent Shell 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 stop_process? +

Register the Persistent Shell MCP server in PolicyLayer and add a rule for stop_process: 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 Persistent Shell MCP. Nothing to install.

What risk level is stop_process? +

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

Can I rate-limit stop_process? +

Yes. Add a rate_limit block to the stop_process 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_process completely? +

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

stop_process is provided by the Persistent Shell MCP server (tntisdial/persistent-shell-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.