rebase_merge_request · Mcp Gitlab MCP: Risk & Policy

WHAT IT DOES

What rebase_merge_request does on Mcp Gitlab

AI agents invoke rebase_merge_request to trigger actions in Mcp Gitlab. 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 rebase_merge_request needs a policy

Rebasing a merge request triggers an external Git operation that rewrites commit history on the branch. This is an Execute-level action as it initiates an asynchronous operation with side effects on the repository. While it can be recoverable in some cases, it is not a simple write and may cause force-push-like effects on the branch.

From the tool's definition Trigger an asynchronous rebase of the MR

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

rebase_merge_request Rate-limited

rebase_merge_request 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": {
    "rebase_merge_request": {
      "limits": [
        {
          "counter": "rebase_merge_request_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 Mcp Gitlab, so you can run agents against it safely.

FAQ

Questions about rebase_merge_request

What does the rebase_merge_request tool do? +

Trigger an asynchronous rebase of the MR. It is categorised as a Execute tool in the Mcp Gitlab MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on rebase_merge_request? +

Register the Mcp Gitlab MCP server in PolicyLayer and add a rule for rebase_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 Mcp Gitlab. Nothing to install.

What risk level is rebase_merge_request? +

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

Can I rate-limit rebase_merge_request? +

Yes. Add a rate_limit block to the rebase_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 rebase_merge_request completely? +

Set action: deny in the PolicyLayer policy for rebase_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 rebase_merge_request? +

rebase_merge_request is provided by the Mcp Gitlab MCP server (wanadev/gitlab-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.