🔍 ReviewPal

AI-powered code review for any language.

Let Claude review your code changes and catch issues before your teammates do.

⏱️ Installation (Step-by-Step)

📖 Detailed Guide: See INSTALL.md for a complete installation guide with troubleshooting.

Step 1: Get Your Anthropic API Key

1. Go to https://console.anthropic.com
2. Sign up or log in
3. Click "Get API Keys"
4. Click "Create Key"
5. Copy the key (starts with sk-ant-...)

💡 Tip: Keep this key secret! Don't commit it to your repo.

Step 2: Add API Key to Your GitHub Repo

1. Go to your GitHub repo (e.g., github.com/yourname/yourrepo)
2. Click Settings (top right)
3. In the left sidebar, click Secrets and variables → Actions
4. Click "New repository secret"
5. Name: ANTHROPIC_API_KEY
6. Value: Paste your API key from Step 1
7. Click "Add secret"

✅ Your API key is now securely stored!

Step 3: Add ReviewPal Workflow to Your Repo

Option A: Quick Install (Terminal)

# Navigate to your repo
cd your-repo

# Create workflow directory
mkdir -p .github/workflows

# Download ReviewPal workflow
curl -o .github/workflows/reviewpal.yml \
  https://raw.githubusercontent.com/Arephan/reviewpal/main/examples/github-action-workflow.yml

# Commit and push
git add .github/workflows/reviewpal.yml
git commit -m "Add ReviewPal workflow"
git push

Option B: Manual Setup (GitHub Web UI)

1. In your repo, click "Add file" → "Create new file"
2. File path: .github/workflows/reviewpal.yml
3. Paste this content:

name: ReviewPal
on:
  pull_request:
    types: [opened, synchronize]

jobs:
  review:
    runs-on: ubuntu-latest
    permissions:
      contents: read
      pull-requests: write
    steps:
      - uses: actions/checkout@v4
        with:
          fetch-depth: 0
      
      - uses: Arephan/reviewpal@v1
        with:
          anthropic_api_key: ${{ secrets.ANTHROPIC_API_KEY }}

4. Click "Commit changes"

Step 4: Test It!

1. Create a new branch: git checkout -b test-reviewpal
2. Make some code changes
3. Commit and push: git push -u origin test-reviewpal
4. Create a Pull Request on GitHub
5. Wait ~30-60 seconds
6. ReviewPal will comment on your PR! 🎉

✅ That's It!

ReviewPal will now automatically review every PR in your repo.

Need help? Open an issue

What It Does

ReviewPal uses Claude AI to:

• ✅ Detect the language automatically (Python, JS, Go, Rust, Java, etc.)
• ✅ Find code quality issues - bugs, anti-patterns, security concerns
• ✅ Spot AI-generated patterns - over-defensive code, verbose comments, over-abstraction
• ✅ Give actionable suggestions - specific fixes, not vague advice

Language agnostic - works with any programming language!

Example Output

## 🔍 ReviewPal

### 📄 `src/api/users.ts`

<details>
<summary>Lines 45-89</summary>

**Language:** TypeScript

**Summary:** Added user authentication with token validation and error handling.

**Issues Found:**

🟡 **Excessive try-catch nesting (4 levels deep)**
💡 *Fix:* Use a single try-catch at the function boundary. Let errors bubble up naturally.

🟡 **Missing input validation before database query**
💡 *Fix:* Add schema validation using zod or joi before the database call.

🟢 **Consider using a constant for the token expiry time**
💡 *Fix:* Move magic number 3600 to a named constant: TOKEN_EXPIRY_SECONDS

</details>

Installation

GitHub Action (Recommended)

name: ReviewPal
on:
  pull_request:
    types: [opened, synchronize]

jobs:
  review:
    runs-on: ubuntu-latest
    permissions:
      contents: read
      pull-requests: write
    steps:
      - uses: actions/checkout@v4
        with:
          fetch-depth: 0
      
      - name: ReviewPal
        uses: Arephan/reviewpal@v1
        with:
          anthropic_api_key: ${{ secrets.ANTHROPIC_API_KEY }}

CLI

npm install -g reviewpal

# Set your API key
export ANTHROPIC_API_KEY=sk-ant-...

# Review staged changes
reviewpal

# Review a git range
reviewpal --git HEAD~3..HEAD

# Pipe from git
git diff main..feature | reviewpal -

Configuration

Action Inputs

| Input | Description | Default | |-------|-------------|---------| | anthropic_api_key | Required - Your Anthropic API key | - | | max_hunks | Max code blocks to analyze | 20 | | model | Claude model to use | claude-sonnet-4-20250514 | | comment_on_pr | Post as PR comment | true |

CLI Options

reviewpal --help

Options:
  -g, --git <range>     Git diff range (e.g., HEAD~3..HEAD)
  -f, --format <type>   Output: friendly, json
  -m, --max-hunks <n>   Max hunks to analyze (default: 20)
  --model <name>        Claude model (default: claude-sonnet-4-20250514)
  -q, --quiet           Minimal output

Supported Languages

All of them! 🌍

ReviewPal uses Claude AI to understand any programming language:

• JavaScript, TypeScript, Python, Java, Go, Rust, C++, C#, Ruby, PHP, Kotlin, Swift...
• Even SQL, YAML, Dockerfile, shell scripts, and more

Claude automatically detects the language and applies appropriate review standards.

How It Works

1. Parse the git diff into code changes
2. Send to Claude with context about the file and change
3. AI analyzes for:
   • Language detection
   • Code quality issues
   • AI-generated patterns
   • Improvement opportunities
4. Format results as friendly PR comments

Why ReviewPal?

Problem: AI-generated code is hard to review

• Over-defensive (try-catch everywhere)
• Over-verbose (obvious comments)
• Over-engineered (unnecessary abstractions)

Solution: Let AI review AI-generated code

• Catches patterns humans miss
• Works with any language
• Gives specific, actionable feedback
• Fast and consistent

🔧 Troubleshooting

ReviewPal isn't commenting on my PRs

Check 1: Is the workflow running?

• Go to your repo → Actions tab
• Look for "ReviewPal" workflow runs
• Click on the latest run to see logs

Check 2: Is the API key set correctly?

• Go to repo Settings → Secrets and variables → Actions
• Verify ANTHROPIC_API_KEY exists
• If not, add it (see Step 2 above)

Check 3: Does the workflow file exist?

• Look for .github/workflows/reviewpal.yml in your repo
• If missing, add it (see Step 3 above)

Check 4: Are there code changes in the PR?

• ReviewPal only analyzes files with code changes
• Empty PRs or README-only changes won't trigger a review

Error: "API initialization failed"

This means the API key is missing or invalid.

Fix:

1. Verify your API key at https://console.anthropic.com
2. Make sure it starts with sk-ant-
3. Re-add it to GitHub Secrets (Settings → Secrets → Actions)
4. Close and reopen your PR to trigger a new run

ReviewPal is too slow

Normal timing:

• Small PR (< 200 lines): 30-60 seconds
• Medium PR (500 lines): 1-2 minutes
• Large PR (1000+ lines): 2-5 minutes

If it's slower:

• Check GitHub Actions status page (status.github.com)
• Check Anthropic API status (status.anthropic.com)
• Reduce max_hunks in the workflow to speed it up

How do I update to the latest version?

Just change @v1 to @v1.1.0 (or latest) in your workflow file:

- uses: Arephan/[email protected]  # specific version
# or
- uses: Arephan/reviewpal@v1      # auto-updates to latest v1.x

Recommendation: Use @v1 to get automatic updates.

Development

# Clone
git clone https://github.com/Arephan/reviewpal
cd reviewpal

# Install
npm install

# Build
npm run build

# Test locally
export ANTHROPIC_API_KEY=sk-ant-...
node dist/index.js --git HEAD~1

API Key Safety

Your ANTHROPIC_API_KEY is:

• ✅ Stored in GitHub Secrets (encrypted)
• ✅ Only accessible to your workflows
• ✅ Never logged or exposed in output
• ✅ Can be rotated anytime at console.anthropic.com

Cost

ReviewPal uses Claude Sonnet 4 by default (~$3 per million tokens).

Typical usage:

• Small PR (100 lines): ~$0.01
• Medium PR (500 lines): ~$0.05
• Large PR (2000 lines): ~$0.20

Set max_hunks to control costs on massive PRs.

Contributing

PRs welcome! Keep it:

1. Language agnostic
2. Actionable (not vague)
3. Friendly in tone

License

MIT

Made with Claude, for reviewing code written by Claude. 🤖