PR Review Agent

An automated GitHub PR review agent powered by the Claude Agent SDK, running in isolated E2B sandboxes with a real-time analytics dashboard.

What it does

1. Receives GitHub webhooks when a PR is opened or updated
2. Spins up an isolated E2B sandbox for each review
3. Runs Claude Agent SDK to analyze the code - it can read files, search the codebase, and run commands
4. Posts a review comment back to the GitHub PR
5. Tracks analytics - cost, tokens, duration, tool usage

Architecture

┌─────────────────┐      ┌──────────────────┐      ┌─────────────────┐
│  GitHub Webhook │─────▶│  Orchestrator    │─────▶│  E2B Sandbox    │
│  (PR opened)    │      │  (Local Express) │      │  (Claude Agent) │
└─────────────────┘      └────────┬─────────┘      └────────┬────────┘
                                  │                         │
                                  ▼                         │
                         ┌──────────────────┐               │
                         │  SQLite + Web UI │◀──────────────┘
                         │  (Analytics)     │
                         └──────────────────┘

Tech Stack

Component	Technology
Runtime	Node.js + TypeScript
Server	Express.js
Agent	@anthropic-ai/claude-agent-sdk
Sandbox	E2B
Database	SQLite (better-sqlite3)
GitHub API	Octokit
Dashboard	Vanilla HTML/JS + Chart.js

Quick Start

1. Install dependencies

npm install

2. Configure environment

cp .env.example .env

Edit .env with your API keys:

ANTHROPIC_API_KEY=sk-ant-...
GITHUB_TOKEN=ghp_...
GITHUB_WEBHOOK_SECRET=your-secret
E2B_API_KEY=e2b_...
PORT=3001

3. Run the server

npm run dev

4. Open the dashboard

Visit http://localhost:3001

5. Trigger a review

Either:

• Use the "Manual Trigger" form in the dashboard with any GitHub PR URL
• Or set up a GitHub webhook (see below)

Setting up GitHub Webhooks

1. Expose your local server with ngrok:

   ngrok http 3001

2. In your GitHub repo, go to Settings → Webhooks → Add webhook

3. Configure:

   • Payload URL: https://your-ngrok-url.ngrok.io/webhook/github
   • Content type: application/json
   • Secret: Same as GITHUB_WEBHOOK_SECRET in your .env
   • Events: Select "Pull requests"

4. Now when you open a PR, the agent will automatically review it!

API Endpoints

Endpoint	Method	Description
/	GET	Analytics dashboard
/webhook/github	POST	GitHub webhook receiver
/api/reviews	GET	List all reviews
/api/reviews/:id	GET	Get review details with traces
/api/analytics	GET	Summary statistics
/api/trigger	POST	Manually trigger a review

How the Agent Works

Inside the E2B sandbox, the Claude Agent SDK:

1. Fetches PR metadata and diff from GitHub
2. Clones the repository
3. Analyzes the changes using tools:
   • Read - read file contents
   • Glob - find files by pattern
   • Grep - search code
   • Bash - run commands
4. Generates a structured review
5. Posts the review as a PR comment

Tracing

The agent captures detailed traces for debugging:

# Get trace events for a review
curl http://localhost:3001/api/reviews | jq '.[0].traceEvents'

Traces include:

• GitHub API call timing
• Git clone duration
• Each tool invocation with inputs/outputs
• Token usage per turn
• Total cost calculation

Project Structure

pr-review-agent/
├── src/
│   ├── index.ts           # Express server + routes
│   ├── orchestrator.ts    # E2B sandbox management + agent code
│   ├── agent/
│   │   └── reviewer.ts    # Standalone agent (reference)
│   ├── analytics/
│   │   ├── store.ts       # SQLite operations
│   │   └── types.ts       # TypeScript interfaces
│   └── web/
│       └── dashboard.html # Analytics UI
├── docs/
│   └── dashboard.png      # Screenshot
├── package.json
├── tsconfig.json
└── .env.example

License

MIT