Skip to main content
Glama
deenesjakoruzh
AmaimaKhalidSethi

Multi-Server FastMCP PR Reviewer

by AmaimaKhalidSethi
OverviewSchemaSourceRelated ServersDiscussionsAdmin
Python
Hybrid

Multi-Server FastMCP PR Reviewer

Zero-cost, multi-server Model Context Protocol (MCP) suite with a unified gateway and a LangGraph automated PR-review agent. Every tool/API used is free-tier eligible (GitHub PAT, Groq LLM).

Architecture

Claude Desktop / Agent
        |
        v
  FastMCP Gateway  (namespaces: code., gh., doc. — dot-separated per MCP tool-naming spec)
   /      |       \
  v       v        v
Code    GitHub   Documentation
Intel   Server   Server (Groq)
(AST+Radon)(PyGithub)
   \       |       /
    Shared Security & Audit Layer
    (API key auth, SQLite WAL, rate limiting)

Related MCP server: GitHub MCP Agent Server

Project layout

mcp-pr-reviewer/
├── core/
│   └── security.py        # auth + rate limit + SQLite audit decorator
├── servers/
│   ├── code_server.py      # AST/radon static analysis (no external API)
│   ├── github_server.py    # PyGithub-backed PR/issue/commit tools
│   └── doc_server.py       # Groq-backed docstring/README/API doc generation
├── gateway/
│   └── gateway.py          # unifies all three servers under code:/gh:/doc: namespaces
├── agent/
│   └── workflow.py         # LangGraph PR-review pipeline (fetch → analyze → doc → publish)
├── data/                    # SQLite audit_log.db lives here (gitignored)
├── docker-compose.yml
├── Dockerfile
├── requirements.txt
├── .env.example
└── claude_desktop_config.example.json

Setup

python -m venv .venv
source .venv/bin/activate        # Windows: .venv\Scripts\activate
pip install -r requirements.txt

cp .env.example .env
# edit .env with your real MCP_API_KEY, GITHUB_TOKEN, GROQ_API_KEY

Load the env vars before running anything locally, e.g.:

export $(grep -v '^#' .env | xargs)   # macOS/Linux

Running

Individual servers (stdio, for local testing)

python servers/code_server.py
python servers/github_server.py
python servers/doc_server.py

Gateway

fastmcp run gateway/gateway.py:gateway

Docker

docker compose up --build

Claude Desktop integration

Copy claude_desktop_config.example.json into your Claude Desktop config (claude_desktop_config.json), fix the absolute path to gateway/gateway.py, and fill in real credentials. Restart Claude Desktop to pick it up.

Testing checklist

1. Schema verification

fastmcp inspect servers/code_server.py
fastmcp inspect servers/github_server.py
fastmcp inspect servers/doc_server.py

2. Security / audit verification

# Should raise 401 Unauthorized
CLIENT_API_KEY=wrong_key python -c "from servers.code_server import analyse_code; analyse_code('x = 1')"

# Inspect the WAL SQLite audit log
sqlite3 data/audit_log.db "SELECT * FROM access_log ORDER BY id DESC LIMIT 5;"

3. End-to-end PR review

python -c "
import asyncio
from agent.workflow import app

async def run():
    result = await app.ainvoke({
        'repo': 'your-username/your-repo',
        'pr_number': 1
    })
    print('Review published:', result['issue_url'])

asyncio.run(run())
"

Notes / things to double-check before you rely on this in production

  • core/security.py's bucket is a single process-wide TokenBucket — every tool across a server shares the same 60/min budget. Split into per-tool or per-client buckets if you need finer-grained limits.

  • secure_tool raises FastAPI's HTTPException, which only maps cleanly to HTTP status codes if the FastMCP transport you're running actually sits behind FastAPI/ASGI. If you run a server over plain stdio, catch this at the MCP layer or replace it with a transport-appropriate exception.

  • Rotate MCP_API_KEY, GITHUB_TOKEN, and GROQ_API_KEY out of .env and into a real secrets manager before any non-local deployment — .env is fine for dev only.

  • GitHub's code search API is capped much lower than the core API (30 req/min vs 5,000 req/hr) — search_repo_code will hit that ceiling first under load.

This server cannot be deployed

One endpoint for every MCP toolRayrun runs every MCP server behind one URL and holds the credentials. Each call is decided per client, tool, and argument, then recorded.ray.runAd

Maintenance

ActivitySlowing
ResponsivenessNo issues

Resources

Related MCP Connectors

Related MCP Servers