Code Review

Fresh Eyes Review

Systematic pre-commit quality gate → checklist-based review → findings → summary.

• Pre-commit code review and quality gates
• Pre-merge pull request reviews
• Systematic code audits before deployment
• Quality verification for critical changes
• Second-opinion review requests

NOT for: quick sanity checks, trivial typo fixes, formatting-only changes

Starting Review

Review Scope: { files/areas under review } Focus Areas: { specific concerns or general quality gate } Checklist: { full or targeted categories }

During Review

Emit findings as discovered:

• {SEVERITY} {FILE_PATH}:{LINE} — { issue description }
• Impact: { consequences if shipped }
• Fix: { concrete remediation }

Completing Review

Review Complete

Findings Summary:

• ◆◆ Severe: {COUNT} — blocking issues
• ◆ Moderate: {COUNT} — should fix before merge
• ◇ Minor: {COUNT} — consider addressing

Recommendation: { ship / fix blockers / needs rework }

{ detailed findings below if any found }

Type Safety

• ✓ No any types without justification comment
• ✓ Null/undefined handled explicitly (optional chaining, nullish coalescing)
• ✓ Type guards used for union types
• ✓ Discriminated unions for state machines
• ✓ Generic constraints specified where needed
• ✓ Return types explicit on public functions
• ✓ No type assertions without safety comment

Error Handling

• ✓ All error paths handled (no silent failures)
• ✓ Meaningful error messages with context
• ✓ Errors propagated or logged appropriately
• ✓ Result types used for expected failures
• ✓ Try/catch blocks have specific error handling
• ✓ Promise rejections handled
• ✓ Resource cleanup in finally blocks

Security

• ✓ User input validated before use
• ✓ No hardcoded secrets or credentials
• ✓ Authentication/authorization checks present
• ✓ Parameterized queries (no SQL injection)
• ✓ XSS prevention (sanitized output)
• ✓ CSRF protection where applicable
• ✓ Sensitive data encrypted/hashed
• ✓ Rate limiting on public endpoints

Testing

• ✓ Tests exist for new functionality
• ✓ Edge cases covered
• ✓ Error scenarios tested
• ✓ Actual assertions (not just execution)
• ✓ No test pollution (proper setup/teardown)
• ✓ Mocks used appropriately (not overused)
• ✓ Test names describe behavior
• ✓ Integration tests for critical paths

Code Quality

• ✓ Names reveal intent (functions, variables, types)
• ✓ Functions <50 lines (single responsibility)
• ✓ Files <500 lines (consider splitting)
• ✓ No magic numbers (use named constants)
• ✓ DRY violations eliminated
• ✓ Nested conditionals <3 deep
• ✓ Cyclomatic complexity reasonable
• ✓ Dead code removed

Documentation

• ✓ Public APIs have JSDoc/TSDoc
• ✓ Complex algorithms explained
• ✓ Non-obvious decisions documented
• ✓ Breaking changes noted
• ✓ TODOs have context and owner
• ✓ README updated if behavior changes
• ✓ Examples provided for complex usage

Performance

• ✓ No obvious N+1 queries
• ✓ Appropriate data structures used
• ✓ Unnecessary allocations avoided
• ✓ Heavy operations async/batched
• ✓ Caching where beneficial
• ✓ Database indexes considered

Rust-Specific (when applicable)

• ✓ rustfmt and clippy passing
• ✓ Result preferred over panic
• ✓ No unwrap/expect outside tests/startup
• ✓ Ownership/borrowing idiomatic
• ✓ Send/Sync bounds respected
• ✓ Unsafe code justified with comments
• ✓ Proper error types (thiserror/anyhow)

1. Announce (activeForm: Announcing review)

Emit starting protocol:

• Scope of review
• Focus areas
• Checklist approach (full or targeted)

2. Checklist (activeForm: Running checklist review)

Systematically verify each category:

• Type Safety → Error Handling → Security → Testing → Quality → Docs → Performance
• Flag violations immediately with severity
• Note clean areas briefly

3. Deep Dive (activeForm: Investigating findings)

For each finding:

• Verify it's actually a problem (not false positive)
• Assess severity and impact
• Determine concrete fix
• Check for pattern across codebase

4. Summarize (activeForm: Compiling review summary)

Emit completion protocol:

• Findings count by severity
• Recommendation (ship / fix blockers / rework)
• Detailed findings list
• Optional: patterns noticed, suggestions for future

Load the maintain-tasks skill for tracking review stages.

{SEVERITY} {FILE_PATH}:{LINE_RANGE}

Issue: { clear description of problem }

Impact: { consequences if shipped — security risk, runtime error, maintenance burden, etc }

Fix: { concrete steps to remediate }

Pattern: { if issue appears multiple times, note scope }

Example:

◆◆ src/auth/login.ts:45-52

Issue: Password compared using == instead of constant-time comparison

Impact: Timing attack vulnerability — attacker can infer password length and content through response timing

Fix: Use crypto.timingSafeEqual() or bcrypt's built-in comparison

Pattern: Single occurrence

◆◆ Severe (blocking):

• Security vulnerabilities
• Data loss risks
• Runtime crashes in common paths
• Breaking changes without migration
• Test failures or missing critical tests

◆ Moderate (should fix):

• Type safety violations
• Unhandled error cases
• Poor error messages
• Missing tests for edge cases
• Significant code quality issues
• Missing documentation for public APIs

◇ Minor (consider addressing):

• Code style inconsistencies
• Overly complex but functional code
• Minor performance optimizations
• Documentation improvements
• TODOs without context
• Naming improvements

Loop: Scan → Verify → Document → Next category

1. Announce review — scope, focus, approach
2. Run checklist — systematically verify each category
3. Document findings — severity, location, issue, impact, fix
4. Investigate patterns — does finding repeat? Broader issue?
5. Deep dive blockers — verify severity assessment, ensure fix is clear
6. Compile summary — counts by severity, recommendation
7. Deliver findings — completion protocol with detailed list

At each finding:

• Verify it's actually a problem
• Assess impact if shipped
• Determine concrete fix
• Note if pattern across files

Before completing review:

Check coverage:

• ✓ All checklist categories verified?
• ✓ Both happy path and error paths reviewed?
• ✓ Tests examined for actual assertions?
• ✓ Security-sensitive areas given extra scrutiny?

Check findings quality:

• ✓ Severity accurately assessed?
• ✓ Impact clearly explained?
• ✓ Fix actionable and concrete?
• ✓ False positives eliminated?

Check recommendation:

• ✓ Aligned with findings severity?
• ✓ Blockers clearly marked?
• ✓ Path forward unambiguous?

ALWAYS:

• Announce review start with scope and focus
• Run systematic checklist, don't skip categories
• Emit findings as discovered, don't batch at end
• Assess severity honestly (err toward caution)
• Provide concrete fixes, not just complaints
• Complete with summary and recommendation
• Mark false positives if checklist item doesn't apply
• Consider patterns (single issue or systemic?)

NEVER:

• Skip checklist review for "quick check"
• Assume code is safe without verification
• Flag style preferences as blockers
• Provide vague findings without fix guidance
• Approve severe findings "for later fix"
• Complete review without announcement protocol
• Miss security checks on user input paths
• Ignore test quality (execution != validation)

Core methodology:

• checklist.md — extended checklist details, examples, severity guidance

Related skills:

• codebase-recon — evidence-based investigation (foundation for review)
• debugging — structured bug investigation