Last updated: January 8, 2026

Context

You have set up CodeRabbit on your GitLab project, added a CODEOWNERS file, and enabled suggested_reviewers and auto_assign_reviewers in your .coderabbit.yaml. However, reviewers are not being consistently suggested or auto-assigned on new merge requests.

Answer

CodeRabbit’s reviewer suggestion and auto-assignment depend on configuration, permissions, and project history. This article is a guide on how to troubleshoot and fix.

Troubleshooting steps

1. Check your configuration

In your .coderabbit.yaml, make sure both settings are present:

reviews:
  suggested_reviewers: true
  auto_assign_reviewers: true

CodeRabbit reads this file from the MR branch, so ensure it is committed there.

2. Verify the CodeRabbit bot’s GitLab access

CodeRabbit’s GitLab token must:

• Have Developer role access to the repo

• Include the api scope

• Be valid and not expired

If unsure, reinstall the integration from CodeRabbit’s GitLab settings.

3. Build reviewer history

Reviewer suggestions rely on past MRs. You need:

• Closed or merged MRs with assigned reviewers or approvers

• Enough historical data for CodeRabbit to identify reviewer patterns

If this is your first few MRs, reviewer suggestions may be inconsistent until more history exists.

4. Use a valid CODEOWNERS file

Place your CODEOWNERS file at the repo root and confirm it maps file paths to valid usernames or groups. This helps CodeRabbit and GitLab understand reviewer ownership.

5. Ensure CodeRabbit actually reviewed the MR

Reviewer suggestion runs only after CodeRabbit has analyzed the MR. If no review comment appears from CodeRabbit, the webhook may not have triggered — push a new commit or reinstall the integration.

Common causes

• Not enough historical MRs with reviewers

• Bot token missing api scope or wrong role

• Misplaced CODEOWNERS file

• .coderabbit.yaml missing or not on the MR branch

Quick setup checklist

1. Verify .coderabbit.yaml includes both reviewer settings.

2. Check bot access (Developer + api scope).

3. Add/validate your CODEOWNERS file.

4. Merge several MRs with reviewers to build history.

5. Confirm CodeRabbit reviews appear on new MRs.