tunnel_restart · LocalAnt MCP: Risk & Policy

WHAT IT DOES

What tunnel_restart does on LocalAnt

AI agents invoke tunnel_restart to trigger actions in LocalAnt. 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 tunnel_restart needs a policy

This tool triggers an external operation that restarts a public tunnel service. While not destructive (the tunnel can be restarted again), it executes a command with side effects that could disrupt active connections or services relying on that tunnel. The effect is not a simple read or write of data, but an active system operation.

From the tool's definition Tool name 'tunnel_restart' and description 'Restart the public tunnel' indicate invocation of an external operation (tunnel service restart) whose effects are not immediately reversible and depend on system state.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

tunnel_restart Rate-limited

tunnel_restart 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": {
    "tunnel_restart": {
      "limits": [
        {
          "counter": "tunnel_restart_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 LocalAnt, so you can run agents against it safely.

FAQ

Questions about tunnel_restart

What does the tunnel_restart tool do? +

Restart the public tunnel. It is categorised as a Execute tool in the LocalAnt MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on tunnel_restart? +

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

What risk level is tunnel_restart? +

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

Can I rate-limit tunnel_restart? +

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

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

tunnel_restart is provided by the LocalAnt MCP server (yuga-hashimoto/localant). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.