repo.run_typecheck · ForLoop MCP: Risk & Policy

WHAT IT DOES

What repo.run_typecheck does on ForLoop MCP

AI agents invoke repo.run_typecheck to trigger actions in ForLoop 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 repo.run_typecheck needs a policy

This tool invokes an external command (typecheck) on a code repository. While typecheck operations are generally safe in intent, they represent code execution that could be maliciously configured or exploited if a repository's configuration is compromised. The blast radius is high because a compromised typecheck command could execute arbitrary logic.

From the tool's definition Tool runs a configured typecheck command, which executes arbitrary code/scripts defined in the repository's configuration.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

repo.run_typecheck Rate-limited

repo.run_typecheck 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": {
    "repo.run_typecheck": {
      "limits": [
        {
          "counter": "repo.run_typecheck_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 ForLoop MCP, so you can run agents against it safely.

FAQ

Questions about repo.run_typecheck

What does the repo.run_typecheck tool do? +

Run only the configured typecheck command, when one is configured. It is categorised as a Execute tool in the ForLoop 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 repo.run_typecheck? +

Register the ForLoop MCP server in PolicyLayer and add a rule for repo.run_typecheck: 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 ForLoop MCP. Nothing to install.

What risk level is repo.run_typecheck? +

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

Can I rate-limit repo.run_typecheck? +

Yes. Add a rate_limit block to the repo.run_typecheck 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 repo.run_typecheck completely? +

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

repo.run_typecheck is provided by the ForLoop MCP server (master0ffate/forloop-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.