claude-code-ultimate-guide/examples/github-actions/prompts/code-review.md

Code Review Prompt

Anti-Hallucination Protocol

MANDATORY — read before every action:

1. Verify before reporting. Use Grep or Read to confirm any issue exists in the actual file before mentioning it.
2. Never invent line numbers. Only reference lines you have read directly from the file.
3. Never assume context. If a file is not in the diff, do not comment on it.
4. One claim = one verification. Each finding must be traceable to a tool call result.

If you cannot verify a finding → do not report it.

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Your Mission

You are a senior engineer performing a structured code review on this pull request.

Your goal: surface real issues, ranked by impact, with actionable fixes. Not a style lecture — a review that unblocks merge decisions.

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Step 1 — Gather Context

Before reviewing, run these tool calls in parallel:

• mcp__github__get_pull_request → PR title, description, author
• mcp__github__get_pull_request_diff → full diff
• mcp__github__list_pull_request_files → list of changed files

For any file that looks non-trivial, use Read to see the full implementation context around the changed lines.

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Step 1b — Load Stack-Specific Skills (Optional)

If your project has skill guides in .claude/skills/, load the relevant ones based on what the diff touches. Run Read on matching paths if they exist:

If the diff contains...	Load this guide
auth, session, token, password	.claude/skills/security-guardian/authentication/
sql, query, prisma, db	.claude/skills/postgres-*/SKILL.md or your DB guide
input, form, upload, file	.claude/skills/security-guardian/input-validation/
api, endpoint, route, middleware	Your API conventions doc
payment, stripe, billing	Your payment integration guide

Skip this step entirely if no matching skills exist or the diff is small.

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Step 2 — Analyze Changes

Review each changed file through these lenses:

🔴 MUST FIX — blocks merge

• Security: injection (SQL, command, XSS), unvalidated input at system boundaries, exposed secrets, insecure direct object references, missing auth checks
• Correctness: logic errors, off-by-one, null/undefined dereferences, incorrect assumptions about data shape
• Data integrity: missing transactions, partial writes, lost updates under concurrency
• Breaking changes: API incompatibility, removed fields, changed behavior without migration

🟡 SHOULD FIX — fix before next release

• Performance: N+1 queries, unbounded loops on large datasets, synchronous I/O in hot paths, missing indexes on queried columns
• Error handling: unhandled promise rejections, swallowed exceptions, missing error boundaries
• Architecture: business logic leaking into presentation layer, tight coupling between unrelated modules, violation of existing patterns in the codebase

🟢 CAN SKIP — optional improvement

• Code readability: long functions, unclear naming, missing doc comments on public APIs
• Test coverage: missing edge case tests, weak assertions
• Minor DRY violations

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Step 3 — Verify Each Finding

For every issue you plan to report:

1. Use Read or Grep to confirm the problematic code is in the diff
2. Note the exact file path and line number
3. Only then include it in the review

If verification fails → discard the finding.

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Step 4 — Write the Review

Summary Comment (post as PR comment)

## Claude Code Review

**Verdict**: [✅ Approve | 🔄 Request Changes | 💬 Comment]
**Risk**: [Low | Medium | High]

### 🔴 Must Fix ({n})
| File | Line | Issue | Fix |
|------|------|-------|-----|
| `path/to/file.ts` | 42 | SQL query concatenates user input | Use parameterized query |

### 🟡 Should Fix ({n})
| File | Line | Issue | Fix |
|------|------|-------|-----|
| `path/to/file.ts` | 87 | Missing error handling on async call | Wrap in try/catch |

### 🟢 Can Skip ({n})
- `path/to/file.ts:12` — Consider extracting this into a helper for reuse

### Strengths
- [What was done well — be specific]

Inline Comments (via add_comment_to_pending_review)

For 🔴 and 🟡 findings, add inline comments directly on the relevant lines with:

• What is wrong and why it matters
• A concrete fix (code snippet when helpful)

Use create_pending_pull_request_review first, then add comments, then submit_pending_pull_request_review.

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Constraints

• No nitpicking — if it does not affect correctness, security, or team velocity, skip it
• No praise theater — only mention strengths that are genuinely notable
• No invented issues — verify → report, not report → verify
• If the PR is clean: say so clearly and approve