EngineeringReviews code changes against your standards
Code reviewer
Connect a repository and it reviews branches and pull requests for bugs, security problems, breaking changes and unclear code, pointing at exact lines with a suggested fix. It runs your tests on its own computer before giving a verdict, and when you want it to, it fixes what it found on a branch of its own and opens a pull request.
- Works with
- GitHub
- Recommended model
- Claude Opus 5.5
- Skills
- 12
What it does
- Reviews diffs, branches and pull requests
- Runs your tests, linter and build before judging
- Points to exact lines with a fix, ranked by how much it matters
- Checks against your rules and flags breaking changes
- Tracks down failing tests to the root cause
- Fixes issues on its own branch and opens a pull request when asked
The skills it brings
Playbooks the mate follows when the job calls for them. You can read and edit every one after adding it.
/eng-code-reviewCode reviewReviewing a diff, branch or pull request: what to check (correctness, security, breaking changes, tests), how to rank findings, how to write comments with exact lines and fixes, and how to respond when your own code gets review feedback.
/eng-repo-setupWorking copy setupGetting a working copy of the person's code on your computer before any engineering task: access (GitHub connector, a token they paste, or a Knowledge folder), cloning, a branch of your own, installing dependencies and a baseline test run.
/eng-verificationVerify before saying doneAbout to say code work is done, fixed, passing or ready (before a commit, a pull request, or a status update to the person): run the command that proves it, read the output, and report what it showed. Evidence before claims.
/eng-systematic-debuggingSystematic debuggingFixing a bug, failing test, broken build or unexpected behaviour in the person's code: find the root cause with evidence before changing anything, prove it with a failing test, fix once, verify. Use before proposing any fix.
/eng-test-driven-developmentTest-driven developmentWriting or changing code in the person's repo (a feature, a bug fix, a refactor, a behaviour change): write the test first, watch it fail for the right reason, write the least code to pass, then clean up, with the whole suite green at the end.
/eng-design-firstDesign before buildingBefore building a feature, a new project or a behaviour change in code: understand what the person wants and why, ask the questions that matter one at a time, compare approaches, and get a short design approved before any code is written.
/eng-writing-plansImplementation plansTurning an agreed design or a clear multi-step request into a written implementation plan before coding: files to touch, small test-first tasks with exact commands, then executing it task by task with progress ticked off in the plan.
/eng-branch-finishFinish a branchFinishing a branch of code work: run the full checks, clean up the diff, review it yourself, update from the base branch, then push and open a pull request with a clear description (or keep it local), as the person chooses.
/eng-pr-triagePR triageWorking through a backlog of open pull requests: categorising by urgency and readiness, spotting blockers, nudging stale ones, assigning reviewers, and producing a triage summary for standup or a weekly review.
/eng-release-notesRelease notesCompiling release notes from git history, merged PRs and issues: categorising what changed, writing for the right audience (user-facing changelog, GitHub release, internal digest), and calling out breaking changes with migration steps.
/eng-bug-reproductionBug reproductionTurning a vague bug report into a minimal, self-contained reproduction: verifying the original report, stripping it to the essential failure, writing a failing test case, and documenting exact steps so any developer can confirm the bug in under two minutes.
/eng-dependency-upgradeDependency upgradeUpgrading project dependencies safely: auditing for vulnerabilities, reading changelogs, upgrading one package at a time, fixing breaking changes, and verifying the full suite still passes.
Things to ask it
Review the latest changes in …Check this diff for security issues: …Find out why this test is failing: …Write our review checklist