code-review-pro

SKILL.md

Code Review Pro

Deep code analysis covering security, performance, maintainability, and best practices.

When to Use This Skill

Activate when the user:

Asks for a code review

Wants security vulnerability scanning

Needs performance analysis

Asks to "review this code" or "audit this code"

Mentions finding bugs or improvements

Wants refactoring suggestions

Requests best practice validation

Instructions

Security Analysis (Critical Priority)

SQL injection vulnerabilities

XSS (cross-site scripting) risks

Authentication/authorization issues

Secrets or credentials in code

Unsafe deserialization

Path traversal vulnerabilities

CSRF protection

Input validation gaps

Insecure cryptography

Dependency vulnerabilities

Performance Analysis

N+1 query problems

Inefficient algorithms (check Big O complexity)

Memory leaks

Unnecessary re-renders (React/Vue)

Missing indexes (database queries)

Blocking operations

Resource cleanup (file handles, connections)

Caching opportunities

Excessive network calls

Large bundle sizes

Code Quality & Maintainability

Code duplication (DRY violations)

Function/method length (should be <50 lines)

Cyclomatic complexity

Unclear naming

Missing error handling

Inconsistent style

Missing documentation

Hard-coded values that should be constants

God classes/functions

Tight coupling

Best Practices

Language-specific idioms

Framework conventions

SOLID principles

Design patterns usage

Testing approach

Logging and monitoring

Accessibility (for UI code)

Type safety

Null/undefined handling

Bugs and Edge Cases

Logic errors

Off-by-one errors

Race conditions

Null pointer exceptions

Unhandled edge cases

Timezone issues

Encoding problems

Floating point precision

Provide Actionable Fixes

Show specific code changes

Explain why change is needed

Include before/after examples

Prioritize by severity

Output Format

# Code Review Report

## 🚨 Critical Issues (Fix Immediately)
### 1. SQL Injection Vulnerability (line X)
**Severity**: Critical
**Issue**: User input directly concatenated into SQL query
**Impact**: Database compromise, data theft

**Current Code:**
```javascript
const query = `SELECT * FROM users WHERE email = '${userEmail}'`;

Fixed Code:

const query = 'SELECT * FROM users WHERE email = ?';
db.query(query, [userEmail]);

Explanation: Always use parameterized queries to prevent SQL injection.

⚠️ High Priority Issues

2. Performance: N+1 Query Problem (line Y)

[Details...]

💡 Medium Priority Issues

3. Code Quality: Function Too Long (line Z)

[Details...]

✅ Low Priority / Nice to Have

4. Consider Using Const Instead of Let

[Details...]

📊 Summary

Total Issues: 12

Critical: 2

High: 4

Medium: 4

Low: 2

🎯 Quick Wins

Changes with high impact and low effort:

[Fix 1]

[Fix 2]

🏆 Strengths

Good error handling in X

Clear naming conventions

Well-structured modules

🔄 Refactoring Opportunities

Extract Method: Lines X-Y could be extracted into calculateDiscount()

Remove Duplication: [specific code blocks]

📚 Resources

OWASP SQL Injection Guide

Performance Best Practices

## Examples

**User**: "Review this authentication code"
**Response**: Analyze auth logic → Identify security issues (weak password hashing, no rate limiting) → Check token handling → Note missing CSRF protection → Provide specific fixes with code examples → Prioritize by severity

**User**: "Can you find performance issues in this React component?"
**Response**: Analyze component → Identify unnecessary re-renders → Find missing useMemo/useCallback → Note large state objects → Check for expensive operations in render → Provide optimized version with explanations

**User**: "Review this API endpoint"
**Response**: Check input validation → Analyze error handling → Test for SQL injection → Review authentication → Check rate limiting → Examine response structure → Suggest improvements with code samples

## Best Practices

- Always prioritize security issues first
- Provide specific line numbers for issues
- Include before/after code examples
- Explain *why* something is a problem
- Consider the language/framework context
- Don't just criticize—acknowledge good code too
- Suggest gradual improvements for large refactors
- Link to documentation for recommendations
- Consider project constraints (legacy code, deadlines)
- Balance perfectionism with pragmatism
- Focus on impactful changes
- Group similar issues together
- Make recommendations actionable