merge_pull_request · Mcp Github MCP: Risk & Policy

WHAT IT DOES

What merge_pull_request does on Mcp Github

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

WHY IT NEEDS A POLICY

Why merge_pull_request needs a policy

This tool modifies repository state by integrating code changes from a pull request into a target branch. While merge operations are reversible (via revert commits), they are significant write operations that alter the main codebase, can affect CI/CD pipelines, and impact all developers working with the repository.

From the tool's definition Merge a pull request. Supports merge, squash, and rebase strategies. Can include a custom commit message and SHA safety check.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

merge_pull_request Rate-limited

merge_pull_request 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": {
    "merge_pull_request": {
      "limits": [
        {
          "counter": "merge_pull_request_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 Mcp Github, so you can run agents against it safely.

FAQ

Questions about merge_pull_request

What does the merge_pull_request tool do? +

Merge a pull request. Supports merge, squash, and rebase strategies. Can include a custom commit message and SHA safety check. It is categorised as a Write tool in the Mcp Github MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on merge_pull_request? +

Register the Mcp Github MCP server in PolicyLayer and add a rule for merge_pull_request: 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 Mcp Github. Nothing to install.

What risk level is merge_pull_request? +

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

Can I rate-limit merge_pull_request? +

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

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

merge_pull_request is provided by the Mcp Github MCP server (sheeryn123/mcp-github-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.