pr-review

name	pr-review
description	Review a GitHub PR and present findings as author-addressed comments. Use when the user asks to review a PR, gives a PR URL or number, or asks for code review feedback on a pull request. Triggers on phrases like "review this PR", "look at this pull request", "code review", or any GitHub PR link.
allowed-tools	Bash, Read, Glob

Input

Accepts a PR URL (e.g. https://github.com/org/repo/pull/123) or a PR number (for the current repo).

Steps

1. Fetch in parallel:

   • gh pr view <pr> --json title,body,files,additions,deletions,baseRefName,headRefName
   • gh pr diff <pr>
   • Check if the repo has a CLAUDE.md (factor its conventions into the review)
   • Only if the user explicitly asks: gh api repos/{owner}/{repo}/pulls/{number}/comments

2. Read the full diff carefully. For large diffs, read persisted output files fully.

3. Write a clear explanation of the PR:

   • What problem does this PR solve and why?
   • What approach was taken — summarize the key changes across files
   • Call out any notable design decisions or trade-offs

4. Review for: bugs, missing error handling, security issues, performance problems, naming/readability, convention violations, lock file anomalies, unsafe casts/patterns.

5. Categorize each finding: High, Medium, Low, or Nit.

Output

Print the review directly — do NOT post comments to the PR unless the user explicitly asks.

Format: H2 title with PR name, then a "What this PR does" section explaining the changes (from step 3), followed by issues listed with severity, file:line reference, and concrete suggestion. End with a "Positives" section noting what was done well.