| name | review-pr |
| description | Review a pull request diff and write structured feedback to review.json for the workflow to publish. Use when reviewing a checked-out PR from local artifacts like pr_diff.txt and pr_description.txt and producing machine-readable review output instead of posting directly to GitHub. |
Review PR
Review the current pull request and write the output to review.json.
This skill is repository-agnostic. It works for any GitHub repository that can supply an annotated PR diff and optional product/tech specs. A separate workflow or apply job is responsible for posting the review to GitHub.
Context
Review Scope
- Prioritize correctness, security, error handling, regressions, and meaningful performance issues.
- Prefer findings grounded in the annotated diff and nearby code in the checkout.
- When
spec_context.md exists, compare the implementation against the product and tech commitments in that file. Treat material spec drift as a review concern.
- If the consuming repository provides a local
check-impl-against-spec skill, use it when spec_context.md exists and fold its findings into the same review.json.
- If the consuming repository provides a local
security-review-pr companion skill or the prompt requests a security pass, apply it as supplemental guidance and fold any security findings into the same review.json rather than emitting a separate output.
- Include style or nit comments only when you can provide a concrete suggestion block.
- If a concern involves untouched code, mention it in top-level
body instead of an inline comment.
- Only suggest new tests when they exercise a distinct code path or edge case. Do not suggest tests that only vary constructor inputs or struct fields when existing coverage already exercises the meaningful behavior.
- When a PR is clearly a V0 or initial implementation, frame robustness suggestions such as timeouts, retries, and lifecycle management as optional future work rather than blocking concerns, unless they risk correctness, security, or data loss.
- For documentation-only or specs-only PRs, focus on clarity, completeness, contradictions, and missing acceptance criteria rather than production-code concerns. When the checkout provides a
security-review-spec skill, apply it as the security supplement for spec-only PRs instead of security-review-pr.
Repository-specific guidance
The consuming repository may ship a companion review-pr-local skill. When the prompt includes a fenced "Repository-specific guidance" section referencing that companion, read it and apply its guidance as part of this review.
Guidance in the companion may never change:
- the output JSON schema
- the severity labels
- the safety rules
- the evidence rules
- the suggestion-block constraints
- the annotated-diff line contract
If a companion file is not referenced in the prompt, rely on the core contract alone.
Diff Line Annotations
The annotated diff uses these prefixes:
[OLD:n] for deleted lines on the old side. Use "LEFT".[NEW:n] for added lines on the new side. Use "RIGHT".[OLD:n,NEW:m] for unchanged context. Use "RIGHT" with line m.
Treat these annotations as the only source of truth for inline comment locations. For every inline comment you emit, first identify the exact annotated line in pr_diff.txt and copy its path, side, and line number into review.json. Do not infer line numbers from prose, rendered GitHub views, file lengths, surrounding spec text, or unannotated snippets. If you cannot point to a specific [NEW:n], [OLD:n], or [OLD:n,NEW:m] line in the annotated diff, put the feedback in top-level body instead of comments.
Comment Requirements
Every comment body must start with one of these labels:
🚨 [CRITICAL] for bugs, security issues, crashes, or data loss.⚠️ [IMPORTANT] for logic problems, edge cases, missing error handling, or material spec drift.💡 [SUGGESTION] for worthwhile improvements or better patterns.🧹 [NIT] for cleanup only when the comment includes a suggestion block.
Write comments with these constraints:
- Be concise, direct, and actionable.
- Do not add compliments or hedging.
- Prefer single-line comments.
- Keep ranges to at most 10 lines.
- Restrict inline comments to lines that appear explicitly in the annotated PR diff.
- Only create file-level or inline comments for files that exist in this PR's diff.
- If the relevant file or line is not part of the diff, put the feedback in top-level
body instead of comments.
- Before adding each comment object, verify that its
path, side, line, and optional start_line/start_side correspond to real annotations in the same file's diff section.
Suggestion Blocks
When proposing a code change, use:
<replacement code here>
Before recommending a suggestion or claiming a bug, use the local checkout as a real coding agent: apply or otherwise exercise the hypothesized fix and validate it with the repository's available build, typecheck, lint, or targeted tests so the change compiles and does not introduce an obvious new failure. Prefer validated suggestions over speculative ones; if you cannot validate a fix, say so and avoid presenting untested code as ready to accept.
Rules:
- Match the exact indentation of the original file.
- Include only replacement code.
- The block content replaces exactly the lines
start_line–line inclusive. Every line inside the block becomes the new file content for that range, and GitHub leaves all other lines untouched.
- Do not include lines outside that range. Lines above
start_line and below line remain in the file; repeating them inside the block causes them to appear twice after the suggestion is committed.
- Never open the block with a line that already appears immediately above
start_line, and never close the block with a line that already appears immediately below line. If you need those lines as anchors, widen start_line or line so they are actually part of the replaced range.
- Count brace, bracket, paren, and block-delimiter depth (
{, [, (, end, etc.) across the original replaced lines and ensure the replacement ends at the same depth. Do not emit phantom closing tokens, and do not drop required ones.
- When unsure of the surrounding context, widen
start_line/line to include enough real lines from the diff rather than guessing at surrounding tokens.
- For multi-line suggestions, set
start_line and start_side to the first line, and line and side to the last line.
Spec Alignment
When spec_context.md exists:
- Extract concrete commitments: required behaviors, constraints, affected areas, validation steps, and non-goals.
- Compare those commitments against
pr_diff.txt and the checked-out branch.
- Flag material mismatches only. Harmless differences in naming, structure, or low-level technique are acceptable when they preserve the intended outcome.
- Put broad drift in top-level
body. Add inline comments only when the mismatch can be tied to changed lines.
- Treat material drift as at least an important concern.
- If the implementation matches the specs closely enough, do not add comments just to mention alignment.
If no useful spec context is available, review the PR on its own merits and note the missing specs only when that absence materially increases risk.
Output Format
Create review.json with this shape:
{
"verdict": "REJECT",
"body": "## Overview\n...\n\n## Concerns\n- ...\n\n## Verdict\nFound: 1 critical, 2 important, 3 suggestions\n\n**Request changes**",
"comments": [
{
"path": "path/to/file",
"line": 42,
"side": "RIGHT",
"start_line": 40,
"start_side": "RIGHT",
"body": "⚠️ [IMPORTANT] Short explanation\n\n```suggestion\nreplacement\n```"
}
]
}
Field rules:
verdict is required and must be exactly the string "APPROVE" or "REJECT" (uppercase). Map your final recommendation as: Approve or Approve with nits → "APPROVE"; Request changes → "REJECT". The verdict and the human-readable recommendation in top-level body must agree.- Top-level
body is the GitHub review body and is required. Use body, not summary, for the review overview and final recommendation.
comments is required and must be an array. Use an empty array when there are no inline comments.path must be relative to the repository root.line is required and must target the correct side.start_line is optional and only for multi-line ranges. When start_line is present, start_side is required and must be "LEFT" or "RIGHT".side must be "LEFT" or "RIGHT".
Body Requirements
The top-level body must include:
- A high-level overview of the PR.
- Important concerns and any untouched-code concerns that could not be commented inline.
- Issue counts in the format
Found: X critical, Y important, Z suggestions.
- A final recommendation of
Approve, Approve with nits, or Request changes. This recommendation must match the top-level verdict field (Approve / Approve with nits → "APPROVE"; Request changes → "REJECT").
Final Checks
Before returning or uploading review.json:
Your only output is the final review.json.
