Code Review

Code Review

When to Use

Use this skill when tasked with reviewing code changes, pull requests, or newly written code before it is accepted.

Review Categories

Procedure

1. Understand the Context

# What is this change supposed to do?
bash /home/shared/scripts/task.sh get "$TASK_ID" | jq -r '.description' 2>/dev/null

# What files changed?
cd ~/workspace
git diff --stat HEAD~1 2>/dev/null || echo "No git history — reviewing all files"
git log --oneline -5 2>/dev/null

# Read the full diff
git diff HEAD~1 2>/dev/null | head -500

2. Correctness Review

Does the code actually work?

TARGET="${1:-~/workspace/src}"

# Check: does it handle the stated requirements?
# (Read the code and trace the logic manually)

# Check: edge cases
echo "=== Potential edge cases ==="
# Null/undefined checks
rg '=== null|== null|=== undefined|== undefined|is None' "$TARGET" --type-add 'code:*.{js,py,ts}' --type code -n | head -10
echo "(Verify every nullable value is checked before use)"

# Array bounds
rg '\[0\]|\[-1\]|\.length\b|len\(' "$TARGET" --type-add 'code:*.{js,py,ts}' --type code -n | head -10
echo "(Verify array access is bounds-checked)"

# Check: error handling
rg 'catch|except|\.catch|on\(.error' "$TARGET" --type-add 'code:*.{js,py,ts}' --type code -n | head -10
echo "(Verify errors are handled, not swallowed)"

# Check: does it return/exit correctly in all paths?
rg 'return |process\.exit|sys\.exit' "$TARGET" --type-add 'code:*.{js,py,ts}' --type code -n | head -10

3. Security Review

echo "=== Security checks ==="

# No hardcoded secrets
rg -n -i '(password|secret|token|api.?key)\s*[:=]\s*["\x27][a-zA-Z0-9]' "$TARGET" \
  --type-add 'code:*.{js,py,ts,sh}' --type code | head -5

# No user input in dangerous functions
rg -n '(eval|exec|system|popen)\s*\(' "$TARGET" --type-add 'code:*.{js,py,ts}' --type code | head -5

# Input validation present
rg -n '(validate|sanitize|escape|parseInt|Number\(|\.trim\(\))' "$TARGET" \
  --type-add 'code:*.{js,py,ts}' --type code | head -10
echo "(Verify user input is validated before use)"

# No path traversal
rg -n '(req\.(params|query|body).*\.(join|resolve|readFile))' "$TARGET" --type js | head -5

4. Performance Review

echo "=== Performance checks ==="

# Nested loops (potential O(n^2))
rg -n 'for.*\{' "$TARGET" --type-add 'code:*.{js,ts}' --type code -A 5 \
  | grep -B 1 'for.*\{' | head -10
echo "(Check if nested loops are necessary)"

# Unbounded growth
rg -n '\.push\(|\.append\(|\.concat\(' "$TARGET" --type-add 'code:*.{js,py,ts}' --type code -B 2 \
  | grep -v 'splice\|pop\|shift\|slice\|limit' | head -10
echo "(Verify arrays/lists have size limits)"

# Resource cleanup
rg -n '(open\(|createReadStream|createConnection|connect\()' "$TARGET" \
  --type-add 'code:*.{js,py,ts}' --type code | head -10
echo "(Verify opened resources are closed — look for .close(), finally, using, with)"

# Synchronous I/O in async code
rg -n '(readFileSync|writeFileSync|execSync)' "$TARGET" --type js | head -5
echo "(Sync I/O blocks the event loop)"

5. Style Review

echo "=== Style checks ==="

# Dead code
rg -n '^\s*(//|#)\s*(function|def |class |const |let |var |import )' "$TARGET" \
  --type-add 'code:*.{js,py,ts,sh}' --type code | head -5
echo "(Commented-out code should be deleted)"

# Console.log left in
rg -n 'console\.(log|debug)\(' "$TARGET" --type-add 'code:*.{js,ts}' --type code \
  | grep -v 'test\|spec' | head -5
echo "(Debug logging should be removed or use proper logger)"

# Naming conventions
rg -n '\b(data|info|temp|tmp|foo|bar|baz|x|y|z)\b\s*=' "$TARGET" \
  --type-add 'code:*.{js,py,ts}' --type code | grep -v 'for\s*(' | head -10
echo "(Vague variable names — consider more descriptive names)"

# Consistent formatting
head -3 $(find "$TARGET" -name '*.js' -o -name '*.py' | head -5) 2>/dev/null
echo "(Check: consistent indentation, semicolons, quote style)"

6. Run Tests

cd ~/workspace
npm test 2>&1 | tail -10 || python3 -m pytest tests/ -v 2>&1 | tail -10
echo "Test exit code: $?"

7. Write the Review

REVIEW_FILE="/home/shared/code-review-$(date +%Y%m%d)-${TASK_ID}.md"

cat > "$REVIEW_FILE" <<'EOF'
# Code Review

**Task:** [task ID and description]
**Reviewer:** [agent name]
**Date:** YYYY-MM-DD
**Verdict:** Approve / Request Changes / Reject

## Summary
[1-2 sentences: overall quality assessment]

## Critical (must fix)
### C1: [title]
- **File:** [path:line]
- **Issue:** [description]
- **Fix:** [specific suggestion]

## Important (should fix)
### I1: [title]
- **File:** [path:line]
- **Issue:** [description]
- **Suggestion:** [specific suggestion]

## Minor (consider)
### M1: [title]
- **File:** [path:line]
- **Note:** [description]

## Positive
- [Something well done — be specific]
- [Good pattern worth noting]

## Test Results
- Tests run: N
- Tests passed: N
- Tests failed: N
EOF

# Register as artifact
bash /home/shared/scripts/artifact.sh register \
  --name "code-review-${TASK_ID}" \
  --type "review" \
  --path "$REVIEW_FILE" \
  --description "Code review for task $TASK_ID"

Quality Checklist

• Context understood (what the change is supposed to do)
• Correctness: logic traced, edge cases considered, error handling verified
• Security: no secrets, no injection, input validated
• Performance: no O(n^2), no unbounded growth, resources closed
• Style: no dead code, consistent formatting, clear naming
• Tests run and results recorded
• Every finding has file, line, issue description, and specific fix suggestion
• Positive aspects acknowledged
• Verdict is clear (approve/request changes/reject)