repo.apply_patch · ForLoop MCP: Risk & Policy

WHAT IT DOES

What repo.apply_patch does on ForLoop MCP

AI agents use repo.apply_patch to create or update resources in ForLoop MCP — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your ForLoop MCP environment.

WHY IT NEEDS A POLICY

Why repo.apply_patch needs a policy

This tool modifies code files through search-and-replace operations. While the changes are technically reversible (can be undone with version control or re-applied patches), the blast radius is high because unvetted patches could corrupt the codebase, break tests, or introduce vulnerabilities across multiple files.

From the tool's definition Tool applies 'search/replace edits inside the workspace' and description explicitly recommends requiring 'approval first', indicating the changes are reversible but potentially wide-reaching code modifications.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

repo.apply_patch Rate-limited

repo.apply_patch stays usable, but capped — an agent stuck in a loop can't make hundreds of changes 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.apply_patch": {
      "limits": [
        {
          "counter": "repo.apply_patch_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}

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.apply_patch

What does the repo.apply_patch tool do? +

Apply exact search/replace edits inside the workspace. The orchestrator should require approval first. It is categorised as a Write tool in the ForLoop MCP MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on repo.apply_patch? +

Register the ForLoop MCP server in PolicyLayer and add a rule for repo.apply_patch: 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.apply_patch? +

repo.apply_patch is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.

Can I rate-limit repo.apply_patch? +

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

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

repo.apply_patch 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.