MCP Production — Model Context Protocol + OpenAI

Production-ready MCP server with FastAPI, Redis session memory, streaming, retries, rate limiting, and structured logging. Managed with uv.

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Project Structure

mcp_production/
├── app/
│   ├── main.py                  # FastAPI app factory
│   ├── config.py                # Centralised settings (pydantic-settings)
│   ├── logger.py                # Structured JSON logging (structlog)
│   ├── api/
│   │   ├── routes.py            # All route handlers
│   │   └── schemas.py           # Pydantic request/response models
│   ├── core/
│   │   ├── mcp_loop.py          # Agentic loop (blocking + streaming)
│   │   └── openai_client.py     # OpenAI client with retry
│   ├── tools/
│   │   ├── base.py              # BaseTool + ToolRegistry
│   │   ├── weather.py           # get_weather tool
│   │   ├── calculator.py        # calculate tool (sympy)
│   │   └── wiki.py              # search_wiki tool
│   └── memory/
│       └── session.py           # Redis-backed session memory
├── tests/
│   ├── test_tools.py            # Tool unit tests
│   └── test_api.py              # API integration tests
├── scripts/
│   ├── run_dev.sh               # Dev server (hot reload)
│   ├── run_prod.sh              # Production server (multi-worker)
│   └── test.sh                  # Run test suite
├── pyproject.toml               # uv project + dependencies
├── .env.example                 # Environment variable template
├── docker-compose.yml           # Local dev stack (app + Redis)
└── Dockerfile                   # Multi-stage Docker build

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Quick Start

1. Install uv

curl -LsSf https://astral.sh/uv/install.sh | sh

2. Clone and set up

git clone <repo>
cd mcp_production

# Install all dependencies
uv sync

# Copy and fill in env vars
cp .env.example .env
# Edit .env — add OPENAI_API_KEY at minimum

3. Start Redis

# Option A: Docker Compose (recommended)
docker-compose up redis -d

# Option B: Local Redis
brew install redis && redis-server

4. Run the server

# Development (hot reload)
bash scripts/run_dev.sh

# Or directly:
uv run uvicorn app.main:app --reload

Server starts at http://localhost:8000 API docs at http://localhost:8000/docs

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API Endpoints

POST /api/v1/chat — Blocking

curl -X POST http://localhost:8000/api/v1/chat \
  -H "Content-Type: application/json" \
  -d '{
    "message": "What is the weather in Tokyo and calculate 17 * 4?",
    "session_id": "user-123"
  }'

Response:

{
  "answer": "The weather in Tokyo is 22°C, sunny. And 17 * 4 = 68.",
  "session_id": "user-123",
  "turns": 2,
  "tools_called": ["get_weather", "calculate"],
  "total_tokens": 312
}

POST /api/v1/chat/stream — Streaming SSE

curl -N -X POST http://localhost:8000/api/v1/chat/stream \
  -H "Content-Type: application/json" \
  -d '{"message": "Search Wikipedia for Python", "session_id": "user-123"}'

Events:

data: {"type": "tool_call",   "name": "search_wiki", "args": {"query": "Python"}}
data: {"type": "tool_result", "name": "search_wiki", "content": "Python is..."}
data: {"type": "token",       "content": "Python "}
data: {"type": "token",       "content": "is a..."}
data: {"type": "done",        "turns": 2, "tools": ["search_wiki"]}

DELETE /api/v1/session/{session_id} — Clear History

curl -X DELETE http://localhost:8000/api/v1/session/user-123

GET /api/v1/tools — List Tools

curl http://localhost:8000/api/v1/tools

GET /api/v1/health — Health Check

curl http://localhost:8000/api/v1/health

---

Adding a New Tool

1. Create app/tools/my_tool.py:

from app.tools.base import BaseTool

class MyTool(BaseTool):
    name = "my_tool"

    def schema(self) -> dict:
        return {
            "type": "function",
            "function": {
                "name": self.name,
                "description": "Does something useful.",
                "parameters": {
                    "type": "object",
                    "properties": {
                        "input": {"type": "string", "description": "Input value"}
                    },
                    "required": ["input"]
                }
            }
        }

    async def execute(self, input: str) -> str:
        return f"Result for: {input}"

2. Register in app/tools/__init__.py:

from app.tools.my_tool import MyTool
registry.register(MyTool())

That's it — the tool is automatically included in all API calls.

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Running Tests

bash scripts/test.sh

# Or with uv directly:
uv run pytest tests/ -v

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Docker (Full Stack)

docker-compose up --build

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Environment Variables

Variable	Default	Description
OPENAI_API_KEY	required	Your OpenAI API key
OPENAI_MODEL	gpt-4o-mini	Model to use
REDIS_URL	redis://localhost:6379	Redis connection URL
SESSION_TTL_SECONDS	3600	Session memory TTL
APP_ENV	development	development or production
RATE_LIMIT_PER_MINUTE	20	Requests per minute per IP
OPENWEATHER_API_KEY	(mock used)	Real weather API key