create_merge_request · GitLab MCP Server MCP: Risk & Policy

WHAT IT DOES

What create_merge_request does on GitLab MCP Server

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

WHY IT NEEDS A POLICY

Why create_merge_request needs a policy

This tool creates a new merge request, which is a write operation that modifies project metadata (adds a new MR record) but does not directly alter repository code or data. The change is reversible—merge requests can be closed, reopened, or modified. While merge requests can eventually lead to code changes if merged, the tool itself only creates the proposal.

From the tool's definition Tool name is 'create_merge_request' and description states 'Create a new merge request in a GitLab project'. Merge requests are reversible code review artifacts that propose changes but do not directly modify the target branch until merged and approved.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

create_merge_request Rate-limited

create_merge_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": {
    "create_merge_request": {
      "limits": [
        {
          "counter": "create_merge_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 GitLab MCP Server, so you can run agents against it safely.

FAQ

Questions about create_merge_request

What does the create_merge_request tool do? +

Create a new merge request in a GitLab project. It is categorised as a Write tool in the GitLab 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 create_merge_request? +

Register the GitLab MCP Server MCP server in PolicyLayer and add a rule for create_merge_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 GitLab MCP Server. Nothing to install.

What risk level is create_merge_request? +

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

Can I rate-limit create_merge_request? +

Yes. Add a rate_limit block to the create_merge_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 create_merge_request completely? +

Set action: deny in the PolicyLayer policy for create_merge_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 create_merge_request? +

create_merge_request is provided by the GitLab MCP Server MCP server (maxkulish/gitlab-mcp-archive). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.