AI-powered code review assistant for GitHub and GitLab pull requests using Chrome's built-in AI APIs. Get instant, comprehensive code reviews with interactive Q&A—all processed locally in your browser with zero configuration.

• 🤖 Comprehensive AI Code Review: 9-section structured analysis covering:

  • Overall assessment and readiness
  • Critical issues (blockers)
  • Potential bugs and logic errors
  • Security vulnerabilities
  • Performance and scalability concerns
  • Code quality and maintainability
  • Architecture and design patterns
  • Style suggestions and nitpicks
  • Positive observations

• 💬 Interactive Q&A: Ask follow-up questions about the review

  • Context-aware answers that reference specific PR code
  • Conversation history maintained across questions
  • Get code examples and actionable solutions

• 📝 Smart Summaries: Generates concise PR overviews using Chrome's Summarizer API

• 🎨 Beautiful UI:

  • Side panel with markdown formatting
  • Syntax highlighting for code blocks
  • Collapsible Q&A section
  • Smooth animations and loading states

• 🔒 Privacy First: All AI processing happens locally using Chrome's Gemini Nano

  • No API keys required
  • No data sent to cloud servers
  • Review proprietary code with confidence

• 🌐 Multi-Platform: Works with both GitHub and GitLab pull requests

• Chrome Version: Chrome 128+ (Canary/Dev) or Chrome 138+ (Stable)
• Operating System: Windows 10/11, macOS 13+, or Linux
• Internet Connection: Required for initial AI model download (~3GB, one-time)
• Storage: At least 22GB free space
• GPU: 4GB+ VRAM recommended

1. Clone or download this repository:

   git clone https://github.com/yourusername/code-review-ai.git

2. Open Chrome and navigate to chrome://extensions/

3. Enable Developer mode (toggle in top right corner)

4. Click "Load unpacked"

5. Select the code-review directory

6. The extension icon should appear in your toolbar

This is critical! The extension won't work without this step.

1. Navigate to chrome://flags in a new tab

2. Search for and enable these two flags:

   Flag 1: Optimization Guide

   • Search for: Enables optimization guide on device
   • Set to: Enabled BypassPerfRequirement

   Flag 2: Prompt API

   • Search for: Prompt API for Gemini Nano with Multimodal Input
   • Set to: Enabled

3. Click the "Relaunch" button that appears at the bottom

4. Chrome will restart with AI features enabled

The first time you use the extension, Chrome needs to download the Gemini Nano model (~3GB). This is a one-time process.

What to expect:

1. Navigate to any GitHub or GitLab PR
2. Click the "AI Review" button
3. The extension will show: "AI model is downloading (5-10 minutes)"
4. The download happens in the background—you can close the tab
5. The extension auto-checks status every 30 seconds
6. Once complete, click "AI Review" again to analyze the PR

To manually check download status:

Open Chrome DevTools Console (F12) and run:

await LanguageModel.availability()
// Returns: "downloadable", "downloading", or "available"

1. Navigate to a Pull Request

   • Open any GitHub PR (e.g., https://github.com/microsoft/vscode/pulls)
   • Or any GitLab merge request

2. Start Review

   • Look for the "AI Review" button in the PR header
   • Click it to start analysis
   • The side panel will open automatically

3. View Results

   • Review appears in structured sections
   • Color-coded tags highlight bugs, security issues, performance concerns
   • Code blocks are syntax highlighted
   • Markdown formatting makes it easy to read

After the review completes, you can ask follow-up questions:

1. Open Q&A Section

   • Scroll down in the side panel
   • Click "💬 Ask Questions About This Review"

2. Ask Questions

   • Type your question (up to 500 characters)
   • Examples:
     • "How do I fix the security vulnerability in section 4?"
     • "Can you explain the N+1 query issue with code examples?"
     • "What's the best way to refactor this for better performance?"
   • Press Ctrl+Enter or click "Ask"

3. Get Contextual Answers

   • AI remembers the PR context and previous review
   • Answers reference specific sections
   • Includes code examples when applicable
   • Conversation history is preserved

4. Continue the Conversation

   • Ask follow-up questions
   • Last 3 Q&As are maintained for context
   • Each new PR review starts a fresh Q&A session

Cause: Chrome AI features not enabled or Chrome version too old

Solution:

1. Check Chrome version: chrome://version/ (need Chrome 128+)
2. Enable both flags in chrome://flags:
   • Enables optimization guide on device → Enabled BypassPerfRequirement
   • Prompt API for Gemini Nano with Multimodal Input → Enabled
3. Relaunch Chrome completely
4. Reload the extension in chrome://extensions/

Cause: Download is still in progress or failed

Solution:

1. Wait 10-15 minutes (download can be slow on slower connections)
2. Check download status in DevTools console:

   await LanguageModel.availability()

3. If stuck, restart Chrome and try again
4. Ensure you have 3GB+ free disk space

Cause: Extension context was invalidated or service worker terminated

Solution:

1. Reload the extension: Go to chrome://extensions/ → Click reload icon
2. Refresh the PR page
3. Try clicking "AI Review" again

Cause: Page not fully loaded or content script failed to inject

Solution:

1. Refresh the PR page
2. Check if you're on the PR "Conversation" or "Files changed" tab
3. Check browser console for errors (F12)
4. Ensure extension is enabled in chrome://extensions/

Cause: PR data not stored or AI API unavailable

Solution:

1. Run a fresh code review first
2. Ensure the review completed successfully
3. Check that the Q&A section appeared after review
4. Verify AI model is available (not downloading)

code-review/
├── manifest.json       # Extension configuration (Manifest V3)
├── background.js       # Service worker for AI API calls
├── content.js          # Content script for PR page injection
├── sidebar.html        # Side panel UI with Q&A interface
├── sidebar.js          # Side panel logic and Q&A handlers
├── styles.css          # Injected styles for PR button
├── icons/              # Extension icons (16, 48, 128px)
└── ABOUT.md            # Project story and journey

background.js

• Handles AI API calls (LanguageModel, Summarizer)
• Dual API pattern support (global & namespaced)
• Service worker keep-alive mechanism
• Q&A context management

content.js

• Injects "AI Review" button into PR pages
• Extracts PR data (title, description, diff)
• Handles GitHub and GitLab DOM differences
• Opens side panel for results

sidebar.js

• Displays review results with markdown formatting
• Manages Q&A conversation state
• Handles user interactions (questions, toggle)
• Auto-saves Q&A history to chrome.storage

1. Load the extension in Chrome (chrome://extensions/)
2. Open any public GitHub PR:
   • Example: https://github.com/microsoft/vscode/pulls
   • Or search for PRs with substantial code changes
3. Click "AI Review" button
4. Open DevTools Console (F12) to see API interactions
5. Test Q&A by asking follow-up questions

The extension supports both Chrome AI API patterns:

// Global pattern (newer)
await LanguageModel.create()
await Summarizer.create()

// Namespaced pattern (older)
await ai.languageModel.create()
await ai.summarizer.create()

Automatic detection ensures compatibility across Chrome versions.

• Chrome Extension Manifest V3: Modern extension architecture
• Chrome Prompt API: Gemini Nano for code analysis and Q&A
• Chrome Summarizer API: PR summary generation
• Vanilla JavaScript: No frameworks—lightweight and fast
• Chrome Storage API: Persistent Q&A history
• Chrome Side Panel API: Dedicated review UI

• Custom review focus (quick scan vs. deep dive)
• Code suggestions with diffs
• Export review reports (PDF, Markdown)
• Keyboard shortcuts (Ctrl+Shift+R for review)

• Support for Bitbucket and Azure DevOps
• Custom rules engine for team-specific patterns
• Review templates for different project types
• PR health score (0-100 quality rating)

• VS Code integration (catch issues pre-commit)
• CI/CD integration (auto-review on PR creation)
• Team learning (improve AI from historical decisions)
• Multi-language expansion (specialized frameworks)

MIT License - See LICENSE for details

Contributions are welcome! Here's how you can help:

1. Report Bugs: Open an issue with detailed reproduction steps
2. Suggest Features: Share your ideas in the issues tab
3. Submit PRs: Fork, create a feature branch, and submit a PR
4. Improve Docs: Help make setup clearer for new users
5. Test: Try the extension on various PR types and report findings

Development Setup:

git clone
cd code-review
# Load extension in chrome://extensions/
# Make changes and reload extension to test

🤖 Powered by Chrome's Built-in AI (Gemini Nano)

⭐ If you find CodeReview AI helpful, please star the repo and share it with your team!