# GitHub PR Reviewer MCP Server

A lightweight **Model Context Protocol (MCP)** server that connects **Codex** with GitHub and Notion. It allows Codex to fetch pull request changes, review code, and save approved reviews to Notion.

## Architecture Diagram

![GitHub PR Reviewer MCP Server Architecture](assets/architecture.png)

## Features

- Fetch pull request details and changed files from GitHub
- Analyse code using Codex
- Identify bugs, security risks, performance issues, and maintainability concerns
- Provide severity levels and recommended fixes
- Save approved reviews to Notion
- Integrate with Codex through FastMCP

## Tech Stack

- Python
- FastMCP
- Codex CLI
- GitHub API
- Notion API
- uv
- python-dotenv

## Setup

Create a `.env` file in the project root:

```env
GITHUB_TOKEN=your_github_token
NOTION_API_KEY=your_notion_api_key
NOTION_PAGE_ID=your_notion_page_id
```

Install the project dependencies:

```bash
uv sync
```

Add the MCP server to Codex:

```powershell
codex mcp add github-pr-reviewer -- uv --directory "C:\path\to\pr_reviewer" run python "src\pr_reviewer\pr_analyzer.py"
```

Verify the MCP server:

```powershell
codex mcp list
```

## Usage

Start Codex:

```powershell
codex
```

Then provide a GitHub pull request URL:

```text
Use the github-pr-reviewer MCP server to review this pull request:

https://github.com/OWNER/REPOSITORY/pull/PR_NUMBER

Fetch the pull request changes and review the code for bugs, security issues,
performance problems, and maintainability concerns. Do not save the review
to Notion until I approve it.
```

After reviewing the result:

```text
I approve this review. Save the complete review to Notion using the
github-pr-reviewer MCP server.
```

## Security

Never commit API tokens or the `.env` file.

Add the following entries to `.gitignore`:

```gitignore
.env
.venv/
__pycache__/
```

## Author

**Badar Rasheed Butt**

AI Engineer