stop_nfproxy_service · Firegex MCP: Risk & Policy

WHAT IT DOES

What stop_nfproxy_service does on Firegex

AI agents invoke stop_nfproxy_service to trigger actions in Firegex. 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_nfproxy_service needs a policy

Stopping a network proxy service is an Execute-category action because it triggers an external operation (stopping the nfproxy engine) whose effects depend on the current system state. While not destructive (the service can be restarted), it disrupts active filtering/security operations.

From the tool's definition The tool 'stop_nfproxy_service' is described as stopping the nfproxy engine — a network filtering/proxy service. This is an operational action that terminates a running system component.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

stop_nfproxy_service Rate-limited

stop_nfproxy_service 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_nfproxy_service": {
      "limits": [
        {
          "counter": "stop_nfproxy_service_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 Firegex, so you can run agents against it safely.

FAQ

Questions about stop_nfproxy_service

What does the stop_nfproxy_service tool do? +

Stop the nfproxy engine. It is categorised as a Execute tool in the Firegex 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_nfproxy_service? +

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

What risk level is stop_nfproxy_service? +

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

Can I rate-limit stop_nfproxy_service? +

Yes. Add a rate_limit block to the stop_nfproxy_service 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_nfproxy_service completely? +

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

stop_nfproxy_service is provided by the Firegex MCP server (umbra2728/firegex-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.