---

name: reviewing-code description: Analyzes code quality, identifies bugs, suggests improvements, and checks adherence to best practices. Use when the user asks for code review, code analysis, quality check, or mentions reviewing code.

Code Reviewer

This skill performs comprehensive code reviews to improve quality, identify issues, and suggest best practices.

When to Use This Skill

Invoke this skill when the user:

• Asks for a code review
• Wants to check code quality
• Needs help identifying bugs or issues
• Requests best practice recommendations
• Mentions code analysis or improvement

Review Process

Step 1: Initial Analysis

Read the code and understand:

1. Purpose and functionality
2. Language and framework used
3. Code structure and organization
4. Dependencies and imports

Step 2: Quality Assessment

Evaluate code across multiple dimensions:

Correctness:

• Logic errors or bugs
• Edge cases handled
• Error handling implemented
• Return values appropriate

Readability:

• Clear variable/function names
• Consistent formatting
• Appropriate comments
• Logical code organization

Performance:

• Efficient algorithms
• No redundant operations
• Appropriate data structures
• Resource management

Security:

• Input validation
• No hardcoded credentials
• SQL injection prevention
• XSS protection (if applicable)

Maintainability:

• DRY principle followed
• Single responsibility
• Low coupling, high cohesion
• Easy to extend

Step 3: Generate Feedback

Provide structured feedback:

Critical Issues (must fix):

• Bugs that cause failures
• Security vulnerabilities
• Data loss risks

Warnings (should fix):

• Performance problems
• Maintainability issues
• Best practice violations

Suggestions (nice to have):

• Code style improvements
• Optimization opportunities
• Alternative approaches

Step 4: Code Examples

For each issue, provide:

1. Location (file:line)
2. Description of problem
3. Why it matters
4. Suggested fix with code example

Review Template

Use this structure for reviews:

Copy## Code Review Summary

**Overall Quality:** [Excellent/Good/Fair/Needs Improvement]
**Lines Reviewed:** [Number]
**Critical Issues:** [Number]
**Warnings:** [Number]
**Suggestions:** [Number]

## Critical Issues

### 1. [Issue Title]
**Location:** file.py:42
**Problem:** [Description]
**Impact:** [Why this matters]
**Fix:**
```language
[Code example of suggested fix]

Warnings

[Same structure as Critical Issues]

Suggestions

[Same structure as Critical Issues]

Positive Observations

• [Good pattern 1]
• [Good pattern 2]

Overall Recommendations

[High-level guidance for improvement]

Copy
## Common Review Patterns

**Pattern 1: Bug Identification**
- Trace execution flow
- Check boundary conditions
- Verify error handling
- Test edge cases mentally

**Pattern 2: Security Review**
- Audit all user inputs
- Check authentication/authorization
- Review data handling
- Examine external calls

**Pattern 3: Performance Analysis**
- Identify bottlenecks
- Check algorithmic complexity
- Review database queries
- Examine loop efficiency

**Pattern 4: Maintainability Check**
- Assess code clarity
- Check for duplication
- Evaluate modularity
- Review documentation

## Language-Specific Checks

**Python:**
- PEP 8 compliance
- Pythonic idioms
- Type hints usage
- Exception handling

**JavaScript/TypeScript:**
- ESLint compatibility
- Async/await usage
- Type safety (TS)
- Modern syntax

**Go:**
- Error handling patterns
- Goroutine safety
- Interface usage
- Idiomatic Go

**Other Languages:**
- Follow language conventions
- Use standard library features
- Apply community best practices

## Example Review

**Input Code:**
```python
def get_user(id):
    user = db.query("SELECT * FROM users WHERE id = " + id)
    return user

Review Output:

Critical Issues

1. SQL Injection Vulnerability Location: example.py:2 Problem: String concatenation in SQL query allows injection attacks Impact: Attacker could execute arbitrary SQL, accessing or deleting data Fix:

Copydef get_user(id):
    user = db.query("SELECT * FROM users WHERE id = ?", (id,))
    return user

Warnings

2. Missing Error Handling Location: example.py:1-3 Problem: No handling for invalid ID or database errors Impact: Function crashes on errors instead of graceful handling Fix:

Copydef get_user(user_id):
    try:
        user = db.query("SELECT * FROM users WHERE id = ?", (user_id,))
        return user if user else None
    except DatabaseError as e:
        logger.error(f"Database error retrieving user {user_id}: {e}")
        return None

Suggestions

3. Parameter Naming Location: example.py:1 Problem: Parameter named id shadows Python built-in Impact: Minor - can cause confusion, not a functional issue Fix:

Copydef get_user(user_id):
    # ... rest of function

Validation Checklist

Before completing review:

• All code sections examined
• Security vulnerabilities identified
• Performance issues noted
• Best practices applied
• Examples provided for fixes
• Positive patterns acknowledged
• Overall recommendations given

Review Scope Options

Quick Review:

• Focus on critical issues only
• Security and correctness
• 5-10 minutes

Standard Review:

• All quality dimensions
• Critical + warnings
• 15-30 minutes

Comprehensive Review:

• All dimensions + suggestions
• Alternative approaches
• Refactoring ideas
• 30+ minutes

Ask the user which scope they prefer if unclear.