gh_pr_merge · GitHub CLI MCP Server MCP: Risk & Policy

WHAT IT DOES

What gh_pr_merge does on GitHub CLI MCP Server

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

WHY IT NEEDS A POLICY

Why gh_pr_merge needs a policy

Merging a pull request is a write operation that irreversibly modifies the target branch by incorporating commits. While the merge itself is technically reversible through a revert commit, it permanently alters repository history and integrated code state, making it more severe than typical write operations.

From the tool's definition Tool name 'gh_pr_merge' and description 'Merge a pull request' indicate the tool modifies repository state by integrating code changes into a branch.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

gh_pr_merge Rate-limited

gh_pr_merge 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": {
    "gh_pr_merge": {
      "limits": [
        {
          "counter": "gh_pr_merge_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 GitHub CLI MCP Server, so you can run agents against it safely.

FAQ

Questions about gh_pr_merge

What does the gh_pr_merge tool do? +

Merge a pull request. It is categorised as a Write tool in the GitHub CLI MCP Server MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on gh_pr_merge? +

Register the GitHub CLI MCP Server MCP server in PolicyLayer and add a rule for gh_pr_merge: 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 GitHub CLI MCP Server. Nothing to install.

What risk level is gh_pr_merge? +

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

Can I rate-limit gh_pr_merge? +

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

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

gh_pr_merge is provided by the GitHub CLI MCP Server MCP server (munch-group/gh-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.