Skill: wpank/code-review (version 1.0.0)

--- name: code-review model: reasoning category: testing description: Systematic code review patterns covering security, performance, maintainability, correctness, and testing — with severity levels, structured feedback guidance, review process, and anti-patterns to avoid. Use when reviewing PRs, establishing review standards, or improving review quality. version: 1.0 --- # Code Review Checklist Thorough, structured approach to reviewing code. Work through each dimension systematically rather than scanning randomly. ## Installation ### OpenClaw / Moltbot / Clawbot ```bash npx clawhub@latest install code-review ``` --- ## Review Dimensions | Dimension | Focus | Priority | |-----------|-------|----------| | Security | Vulnerabilities, auth, data exposure | Critical | | Performance | Speed, memory, scalability bottlenecks | High | | Correctness | Logic errors, edge cases, data integrity | High | | Maintainability | Readability, structure, future-proofing | Medium | | Testing | Coverage, quality, reliability of tests | Medium | | Accessibility | WCAG compliance, keyboard nav, screen readers | Medium | | Documentation | Comments, API docs, changelog entries | Low | --- ## Security Checklist Review every change for these vulnerabilities: - [ ] **SQL Injection** — All queries use parameterized statements or an ORM; no string concatenation with user input - [ ] **XSS** — User-provided content is escaped/sanitized before rendering; `dangerouslySetInnerHTML` or equivalent is justified and safe - [ ] **CSRF Protection** — State-changing requests require valid CSRF tokens; SameSite cookie attributes are set - [ ] **Authentication** — Every protected endpoint verifies the user is authenticated before processing - [ ] **Authorization** — Resource access is scoped to the requesting user's permissions; no IDOR vulnerabilities - [ ] **Input Validation** — All external input (params, headers, body, files) is validated for type, length, format, and range on the server side - [ ] **Secrets Management** — No API keys, passwords, tokens, or credentials in source code; secrets come from environment variables or a vault - [ ] **Dependency Safety** — New dependencies are from trusted sources, actively maintained, and free of known CVEs - [ ] **Sensitive Data** — PII, tokens, and secrets are never logged, included in error messages, or returned in API responses - [ ] **Rate Limiting** — Public and auth endpoints have rate limits to prevent brute-force and abuse - [ ] **File Upload Safety** — Uploaded files are validated for type and size, stored outside the webroot, and served with safe Content-Type headers - [ ] **HTTP Security Headers** — Content-Security-Policy, X-Content-Type-Options, Strict-Transport-Security are set --- ## Performance Checklist - [ ] **N+1 Queries** — Database access patterns are batched or joined; no loops issuing individual queries - [ ] **Unnecessary Re-renders** — Components only re-render when their relevant state/props change; memoization is applied where measurable - [ ] **Memory Leaks** — Event listeners, subscriptions, timers, and intervals are cleaned up on unmount/disposal - [ ] **Bundle Size** — New dependencies are tree-shakeable; large libraries are loaded dynamically; no full-library imports for a single function - [ ] **Lazy Loading** — Heavy components, routes, and below-the-fold content use lazy loading / code splitting - [ ] **Caching Strategy** — Expensive computations and API responses use appropriate caching (memoization, HTTP cache headers, Redis) - [ ] **Database Indexing** — Queries filter/sort on indexed columns; new queries have been checked with EXPLAIN - [ ] **Pagination** — List endpoints and queries use pagination or cursor-based fetching; no unbounded SELECT * - [ ] **Async Operations** — Long-running tasks are offloaded to background jobs or queues rather than blocking request threads - [ ] **Image & Asset Optimization** — Images are properly sized, use modern formats (WebP/AVIF), and leverage CDN delivery --- ## Correctness Checklist - [ ] **Edge Cases** — Empty arrays, empty strings, zero values, negative numbers, and maximum values are handled - [ ] **Null/Undefined Handling** — Nullable values are checked before access; optional chaining or guards prevent runtime errors - [ ] **Off-by-One Errors** — Loop bounds, array slicing, pagination offsets, and range calculations are verified - [ ] **Race Conditions** — Concurrent access to shared state uses locks, transactions, or atomic operations - [ ] **Timezone Handling** — Dates are stored in UTC; display conversion happens at the presentation layer - [ ] **Unicode & Encoding** — String operations handle multi-byte characters; text encoding is explicit (UTF-8) - [ ] **Integer Overflow / Precision** — Arithmetic on large numbers or currency uses appropriate types (BigInt, Decimal) - [ ] **Error Propagation** — Errors from async calls and external services are caught and handled; promises are never silently swallowed - [ ] **State Consistency** — Multi-step mutations are transactional; partial failures leave the system in a valid state - [ ] **Boundary Validation** — Values at the boundaries of valid ranges (min, max, exactly-at-limit) are tested --- ## Maintainability Checklist - [ ] **Naming Clarity** — Variables, functions, and classes have descriptive names that reveal intent - [ ] **Single Responsibility** — Each function/class/module does one thing; changes to one concern don't ripple through unrelated code - [ ] **DRY** — Duplicated logic is extracted into shared utilities; copy-pasted blocks are consolidated - [ ] **Cyclomatic Complexity** — Functions have low branching complexity; deeply nested chains are refactored - [ ] **Error Handling** — Errors are caught at appropriate boundaries, logged with context, and surfaced meaningfully - [ ] **Dead Code Removal** — Commented-out code, unused imports, unreachable branches, and obsolete feature flags are removed - [ ] **Magic Numbers & Strings** — Literal values are extracted into named constants with clear semantics - [ ] **Consistent Patterns** — New code follows the conventions already established in the codebase - [ ] **Function Length** — Functions are short enough to understand at a glance; long functions are decomposed - [ ] **Dependency Direction** — Dependencies point inward (infrastructure to domain); core logic does not import from UI or framework layers --- ## Testing Checklist - [ ] **Test Coverage** — New logic paths have corresponding tests; critical paths have both happy-path and failure-case tests - [ ] **Edge Case Tests** — Tests cover boundary values, empty inputs, nulls, and error conditions - [ ] **No Flaky Tests** — Tests are deterministic; no reliance on timing, external services, or shared mutable state - [ ] **Test Independence** — Each test sets up its own state and tears it down; test order does not affect results - [ ] **Meaningful Assertions** — Tests assert on behavior and outcomes, not implementation details - [ ] **Test Readability** — Tests follow Arrange-Act-Assert; test names describe the scenario and expected outcome - [ ] **Mocking Discipline** — Only external boundaries (network, DB, filesystem) are mocked - [ ] **Regression Tests** — Bug fixes include a test that reproduces the original bug and proves it is resolved --- ## Review Process Work through the code in three passes. Do not try to catch everything in one read. | Pass | Focus | Time | What to Look For | |------|-------|------|------------------| | First | High-level structure | 2-5 min | Architecture fit, file organization, API design, overall approach | | Second | Line-by-line detail | Bulk | Logic errors, security issues, performance problems, edge cases | | Third | Edge cases & hardening | 5 min | Failure modes, concurrency, boundary values, missing tests | ### First Pass (2-5 minutes) 1. Read the PR description and linked issue 2. Scan the file list — does the change scope make sense? 3. Check the overall approach — is this the right solution to the problem? 4. Verify the change does not introduce architectural drift ### Second Pass (bulk of review time) 1. Read each file diff top to bottom 2. Check every function change against the checklists above 3. Verify error handling at every I/O boundary 4. Flag anything that makes you pause — trust your instincts ### Third Pass (5 minutes) 1. Think about what could go wrong in production 2. Check for missing tests on the code paths you flagged 3. Verify rollback safety — can this change be reverted without data loss? 4. Confirm documentation and changelog are updated if needed --- ## Severity Levels Classify every comment by severity so the author knows what blocks merge. | Level | Label | Meaning | Blocks Merge? | |-------|-------|---------|---------------| | Critical | `[CRITICAL]` | Security vulnerability, data loss, or crash in production | Yes | | Major | `[MAJOR]` | Bug, logic error, or significant performance regression | Yes | | Minor | `[MINOR]` | Improvement that would reduce future maintenance cost | No | | Nitpick | `[NIT]` | Style preference, naming suggestion, or trivial cleanup | No | Always prefix your review comment with the severity label. This removes ambiguity about what matters. --- ## Giving Feedback ### Principles - **Be specific** — Point to the exact line and explain the issue, not just "this is wrong" - **Explain why** — State the risk or consequence, not just the rule - **Suggest a fix** — Offer a concrete alternative or code snippet when possible - **Ask, don't demand** — Use questions for subjective points: "What do you think about...?" - **Acknowledge good work** — Call out clean solutions, clever optimizations, or thorough tests - **Separate blocking from non-blocking** — Use severity labels so the author knows what matters ### Example Comments **Bad:** > This is wrong. Fix it. **Good:** > `[MAJOR]` This query interpolates user input directly into the SQL string (line 42), which is vulnerable to SQL injection. Consider using a parameterized query: > ```sql > SELECT * FROM users WHERE id = $1 > ``` **Bad:** > Why didn't you add tests? **Good:** > `[MINOR]` The new `calculateDiscount()` function has a few branching paths — could we add tests for the zero-quantity and negative-price edge cases to prevent regressions? **Bad:** > I would have done this differently. **Good:** > `[NIT]` This works well. An alternative approach could be extracting the retry logic into a shared `withRetry()` wrapper — but that's optional and could be a follow-up. --- ## Review Anti-Patterns Avoid these common traps that waste time and damage team trust: | Anti-Pattern | Description | |--------------|-------------| | **Rubber-Stamping** | Approving without reading. Creates false confidence and lets bugs through. | | **Bikeshedding** | Spending 30 minutes debating a variable name while ignoring a race condition. | | **Blocking on Style** | Refusing to approve over formatting that a linter should enforce automatically. | | **Gatekeeping** | Requiring your personal preferred approach when the submitted one is correct. | | **Drive-by Reviews** | Leaving one vague comment and disappearing. Commit to following through. | | **Scope Creep Reviews** | Requesting unrelated refactors that should be separate PRs. | | **Stale Reviews** | Letting PRs sit for days. Review within 24 hours or hand off to someone else. | | **Emotional Language** | "This is terrible" or "obviously wrong." Critique the code, not the person. | --- ## NEVER Do 1. **NEVER approve without reading every changed line** — rubber-stamping is worse than no review 2. **NEVER block a PR solely for style preferences** — use a linter; humans review logic 3. **NEVER leave feedback without a severity level** — ambiguity causes wasted cycles 4. **NEVER request changes without explaining why** — "fix this" teaches nothing 5. **NEVER review more than 400 lines in one sitting** — comprehension drops sharply; break large PRs into sessions 6. **NEVER skip the security checklist** — one missed vulnerability outweighs a hundred style nits 7. **NEVER make it personal** — review the code, never the coder; assume good intent

path: README.md
content: # Code Review Checklist

Systematic code review patterns covering security, performance, maintainability, correctness, and testing — with severity levels, structured feedback guidance, review process, and anti-patterns to avoid.

## What's Inside

- Review dimensions with priority ranking (Security → Performance → Correctness → Maintainability → Testing → Accessibility → Documentation)
- Security checklist (SQL injection, XSS, CSRF, auth, secrets, rate limiting)
- Performance checklist (N+1 queries, re-renders, memory leaks, bundle size, caching)
- Correctness checklist (edge cases, null handling, race conditions, timezone handling)
- Maintainability checklist (naming, SRP, DRY, dead code, dependency direction)
- Testing checklist (coverage, edge cases, flaky tests, mocking discipline)
- Three-pass review process (high-level → line-by-line → edge cases)
- Severity levels (Critical, Major, Minor, Nitpick) with merge-blocking guidance
- Feedback principles and example comments
- Review anti-patterns to avoid

## When to Use

- Reviewing pull requests or merge requests
- Establishing review standards for a team
- Improving the quality and consistency of code reviews
- Training new reviewers on what to look for

## Installation

```bash
npx add https://github.com/wpank/ai/tree/main/skills/testing/code-review
```

### OpenClaw / Moltbot / Clawbot

```bash
npx clawhub@latest install code-review
```

### Manual Installation

#### Cursor (per-project)

From your project root:

```bash
mkdir -p .cursor/skills
cp -r ~/.ai-skills/skills/testing/code-review .cursor/skills/code-review
```

#### Cursor (global)

```bash
mkdir -p ~/.cursor/skills
cp -r ~/.ai-skills/skills/testing/code-review ~/.cursor/skills/code-review
```

#### Claude Code (per-project)

From your project root:

```bash
mkdir -p .claude/skills
cp -r ~/.ai-skills/skills/testing/code-review .claude/skills/code-review
```

#### Claude Code (global)

```bash
mkdir -p ~/.claude/skills
cp -r ~/.ai-skills/skills/testing/code-review ~/.claude/skills/code-review
```

## Related Skills

- [clean-code](../clean-code/) — Coding standards that reviews enforce
- [quality-gates](../quality-gates/) — Automated quality checkpoints in CI/CD
- [testing-patterns](../testing-patterns/) — Testing standards to check during review

---

Part of the [Testing](..) skill category.


Security scan verdicts — ClawScan: clean | static analysis: clean | VirusTotal: clean | SkillSpector: clean (LOW)