| name | gerrit-review |
| description | Use when reviewing a Gerrit change — fetching change details, reading diffs, posting inline comments, and voting with labels. Triggers on "review this Gerrit change", "review change 12345", "look at this Gerrit CL", "code review on Gerrit". |
Gerrit Code Review
Guide for reviewing changes on a Gerrit instance using the Gerrit MCP server tools.
Prerequisites
The Gerrit MCP server must be available (credentials configured via Integrations page). If mcp__gerrit__* tools are not listed, the user needs to connect their Gerrit instance first.
Workflow
1. Fetch the change
Use mcp__gerrit__fetch_gerrit_change with the change ID (numeric or change-Id).
Extract from the response:
- Subject and commit message — understand what the change does
- Owner — who authored it
- Status — NEW (open), MERGED, ABANDONED
- Current patch set number — the latest revision
- Files changed — list of modified files with insertions/deletions
- Existing comments — what reviewers have already said
- Labels — current votes (Code-Review, Verified, etc.)
2. Read the diffs
Use mcp__gerrit__fetch_patchset_diff to compare patch sets or view the current diff.
- To see the full change: compare patch set 1 vs current (or base vs current)
- To see what changed between review rounds: compare two specific patch sets
- Filter by file path if the change is large — focus on the most impactful files first
3. Analyze and form review feedback
Apply standard code review principles:
- Correctness — does the logic do what the commit message claims?
- Edge cases — missing null checks, boundary conditions, error handling
- Style — follows project conventions (check CLAUDE.md if available)
- Security — no credentials in code, proper input validation, no injection vectors
- Performance — unnecessary allocations, N+1 queries, missing caching
4. Post the review
Use mcp__gerrit__submit_gerrit_review to post feedback:
- message: A summary of your review findings (top-level comment)
- labels: Vote appropriately:
Code-Review +1 — looks good but someone else should also review
Code-Review +2 — approved, ready to submit (only if you have authority)
Code-Review -1 — needs changes before merging
Code-Review -2 — blocks submission (serious issues)
Verified +1 — tests pass, builds clean
- comments: Inline comments on specific files and lines
Gerrit conventions
- Attention set: After reviewing, the change owner gets added to the attention set automatically. Don't manually manage attention set unless needed.
- Patchset iteration: When the owner uploads a new patch set addressing your comments, re-review by comparing the previous and new patch sets (
fetch_patchset_diff), not re-reading the entire change.
- Resolved comments: In Gerrit, comments can be marked as "resolved" or "unresolved". Focus on unresolved comments when re-reviewing.
- Vote semantics: Code-Review -2 is a hard block — use it only for architectural issues or security problems, not style nits.
Error handling
- If the change ID is not found, verify the instance name and change number
- If authentication fails, suggest the user reconnect via the Integrations page
- If the MCP server is not available, check that Gerrit credentials are configured