pr-review

name	pr-review
description	Use this skill when the user asks to do a code review for a pull request, review a PR, or review a GitHub PR URL. This includes phrases like "do a code review for this PR", "review PR

When the user asks to review a pull request, follow these steps to review the diff and post inline comments directly to GitHub.

1. Resolve the PR number

Extract the PR number from the user's message (strip any URL prefix). If unclear, ask.

2. Gather metadata

gh pr view <number> --json headRefOid,baseRepository,title

You need:

• headRefOid — full 40-char SHA (required by the review API)
• baseRepository.nameWithOwner — e.g. appspace/helix

3. Fetch the diff

gh pr diff <number>

4. Calculate new-file line numbers

Each hunk starts with @@ -old_start,old_count +new_start,new_count @@. The new_start value is the line number in the new file for the first line of that hunk. Count down from it — both unchanged context lines and + added lines increment the counter. Removed - lines do not. Use this to find the exact new-file line for any + line you want to annotate.

5. Review the diff

Flag only real issues a senior engineer would call out:

• Bugs: logic errors, race conditions, incorrect null/edge-case handling
• Security: injection, unsafe deserialization, secrets in code, auth bypass
• Correctness: does the code do what it claims?

Do not flag:

• Style, formatting, naming — a linter handles those
• Pre-existing issues not introduced by this PR
• Speculative problems with no evidence they occur in practice
• Missing test coverage unless obviously critical

For each issue record: path, line (new-file line number), and a body with a clear explanation and concrete fix.

6. Write the review JSON to a temp file

Always use the Write tool — never a heredoc or inline shell string. Backticks inside Markdown code fences in heredocs are shell-expanded and will cause errors.

Write to /tmp/review-<number>.json:

{
  "commit_id": "<full headRefOid>",
  "body": "Brief overall summary (1-2 sentences).",
  "event": "COMMENT",
  "comments": [
    {
      "path": "src/foo.ts",
      "line": 42,
      "side": "RIGHT",
      "body": "**Issue title**\n\nExplanation and suggested fix."
    }
  ]
}

• side is always "RIGHT" (the new version of the file)
• line must target a + line or unchanged context line — never a - line
• Put all comments in one call to keep them in a single review thread
• If there are no real issues, post with an empty comments array and a clean summary in body

7. Post the review

gh api repos/<owner>/<repo>/pulls/<number>/reviews \
  --method POST \
  --input /tmp/review-<number>.json

Report the returned html_url to the user.