My Claude code review workflow catches things I always miss manually

#!/usr/bin/env python3
# ai-review.py

import subprocess
import sys
import anthropic

client = anthropic.Anthropic()

REVIEW_SYSTEM = """You are a senior software engineer doing a thorough code review.

Review the provided diff for:

1. SECURITY: Injection vulnerabilities, hardcoded secrets, missing auth checks,
   sensitive data in logs, IDOR vulnerabilities

2. CORRECTNESS: Missing error handling, unhandled edge cases, off-by-one errors,
   missing null checks, race conditions

3. PERFORMANCE: N+1 queries, missing indexes implied by new queries,
   unnecessary re-renders (React), blocking I/O in async code

4. API DESIGN: Inconsistent naming, breaking changes, missing validation,
   inconsistent error response shapes

5. TESTS: Missing tests for new behavior, tests that don't cover edge cases

Format your response as:
## Issues Found

For each issue:
**[SEVERITY: HIGH/MEDIUM/LOW]** [Category]: Description
File: `filename:line_number`
```
relevant code snippet
```
Suggestion: How to fix it

## Looks Good
Brief note on what is well-implemented.

If no issues found in a category, skip it.
Focus on real problems, not style preferences."""


def get_diff(base: str = "main") -> str:
    result = subprocess.run(
        ["git", "diff", f"{base}...HEAD", "--unified=5"],
        capture_output=True, text=True
    )
    return result.stdout


def review_diff(diff: str, focus: str | None = None) -> str:
    system = REVIEW_SYSTEM
    if focus:
        system += f"

Focus extra attention on: {focus}"
    
    # Truncate large diffs
    if len(diff) > 60_000:
        diff = diff[:60_000] + "

[Diff truncated at 60K chars]"
    
    response = client.messages.create(
        model="claude-opus-4-5",
        max_tokens=2000,
        system=system,
        messages=[{
            "role": "user",
            "content": f"Review this git diff:

{diff}"
        }]
    )
    return response.content[0].text


if __name__ == "__main__":
    base = sys.argv[1] if len(sys.argv) > 1 else "main"
    focus = sys.argv[2] if len(sys.argv) > 2 else None
    
    diff = get_diff(base)
    if not diff.strip():
        print("No changes to review")
        sys.exit(0)
    
    print("Running AI code review...
")
    review = review_diff(diff, focus)
    print(review)

# .git/hooks/pre-push
#!/bin/bash

echo "Running AI code review..."
python3 ~/bin/ai-review.py main

echo ""
echo "Review complete. Press Enter to continue push, Ctrl+C to cancel."
read

chmod +x .git/hooks/pre-push

# Focus on security for auth-related changes
python3 ~/bin/ai-review.py main "authentication, authorization, and JWT handling"

# Focus on database performance for schema changes  
python3 ~/bin/ai-review.py main "database query patterns, missing indexes, lock implications"

# Focus on React patterns
python3 ~/bin/ai-review.py main "React hook rules, unnecessary re-renders, missing keys"

# .github/workflows/ai-review.yml
name: AI Code Review

on:
  pull_request:
    types: [opened, synchronize]

jobs:
  review:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
        with:
          fetch-depth: 0

      - name: Run AI review
        env:
          ANTHROPIC_API_KEY: ${{ secrets.ANTHROPIC_API_KEY }}
        run: |
          pip install anthropic
          git diff origin/main...HEAD > /tmp/diff.txt
          python3 scripts/ai-review.py /tmp/diff.txt > /tmp/review.txt
          cat /tmp/review.txt

      - name: Post review as comment
        uses: actions/github-script@v7
        with:
          script: |
            const fs = require('fs');
            const review = fs.readFileSync('/tmp/review.txt', 'utf8');
            await github.rest.issues.createComment({
              owner: context.repo.owner,
              repo: context.repo.repo,
              issue_number: context.issue.number,
              body: '## 🤖 AI Code Review

' + review
            });