MCP Server Template

A production-ready FastMCP server template with dual-mode support: secure web deployment with HTTPS and OAuth for Claude Code, or local development with stdio transport for Claude Desktop. This template provides a foundation for building MCP servers that work in both local and production environments.

Features

• 🔄 Dual Mode Support: Local development (stdio) + Production deployment (HTTPS/OAuth)
• 🖥️ Claude Desktop Compatible: Local mode with stdio transport for desktop development
• 🌐 Claude Code Ready: Web mode with SSE transport for production use
• 🔒 OAuth 2.1 + PKCE: Google OAuth 2.1 with PKCE for enhanced security (web mode)
• 🔄 Dynamic Client Registration: RFC 7591 compliant for Claude Code compatibility
• 🌐 HTTPS Support: SSL/TLS encryption with Let's Encrypt integration
• 🐳 Docker Deployment: Production-ready containerized deployment
• ⚡ FastMCP Integration: Built on the modern FastMCP framework
• 🛡️ Security First: JWT tokens, PKCE validation, and comprehensive OAuth endpoints

Example Tools & Resources

• Addition tool: Demonstrates basic tool functionality
• Secret word tool: Shows authenticated tool access
• Dynamic greeting resource: Example of parametrized resources

Quick Start

Prerequisites

For Local Development (Claude Desktop):

• Python 3.10+
• Claude Desktop

For Web Deployment (Claude Code):

• Python 3.10+
• Docker
• A domain name (for HTTPS deployment)
• Browser access (required for OAuth authentication)

1. Clone and Setup

git clone https://github.com/your-username/mcp-server-template.git
cd mcp-server-template

# Install dependencies
pip install uv
uv sync

2. Configure Google OAuth

1. Go to Google Cloud Console
2. Create a new project or select existing
3. Enable Google+ API
4. Create OAuth 2.0 credentials:
   • Application type: Web application
   • Authorized redirect URIs: https://your-domain.com:8443/callback

3. Configure Environment

Create a .env file:

# Server Configuration
SERVER_NAME=mcp-template       # Name for the MCP server, Docker image, and container

# OAuth Configuration
GOOGLE_CLIENT_ID=your-google-client-id.apps.googleusercontent.com
GOOGLE_CLIENT_SECRET=your-google-client-secret
OAUTH_REDIRECT_URI=https://your-domain.com:8443/callback
JWT_SECRET_KEY=your-secure-random-string-here

# SSL/HTTPS (for production)
SSL_ENABLED=true
DOMAIN_NAME=your-domain.com
SSL_CERT_PATH=/etc/letsencrypt/live/your-domain.com/fullchain.pem
SSL_KEY_PATH=/etc/letsencrypt/live/your-domain.com/privkey.pem

# MCP Configuration
MCP_TRANSPORT=sse
MCP_HOST=0.0.0.0
MCP_PORT=8443

4. Deploy

Local Development

# Run locally without SSL
MCP_TRANSPORT=sse SSL_ENABLED=false uv run python server.py

Production Deployment

# Build Docker image
./scripts/build.sh

# Deploy with HTTPS and Let's Encrypt
export DOMAIN_NAME=your-domain.com
export SSL_EMAIL=admin@your-domain.com
export GOOGLE_CLIENT_ID=your-google-client-id.apps.googleusercontent.com
export GOOGLE_CLIENT_SECRET=your-google-client-secret
export OAUTH_REDIRECT_URI=https://your-domain.com:8443/callback
export JWT_SECRET_KEY=$(openssl rand -base64 32)
sudo -E ./scripts/run-with-letsencrypt.sh

Your server will be available at: https://your-domain.com:8443/sse

Using This Template

For Template Users

1. Fork this repository

2. Update server.py:

   • Replace example tools with your own tools
   • Update the server name in FastMCP("YourServerName")
   • Add your custom resources

3. Update pyproject.toml:

   • Change name to your project name
   • Update description
   • Add any additional dependencies

4. Configure deployment:

   • Set up Google OAuth credentials
   • Configure your domain name and OAuth redirect URI
   • Generate a secure JWT secret key

Example Tool Implementation

@mcp.tool()
def my_custom_tool(param1: str, param2: int) -> str:
    """Your custom tool description"""
    # Your tool logic here
    return f"Result: {param1} with {param2}"

@mcp.resource("my-resource://{id}")
def get_my_resource(id: str) -> str:
    """Your custom resource description"""
    # Your resource logic here
    return f"Resource data for {id}"

Client Setup

Claude Desktop (Local Mode)

For local development with Claude Desktop (no OAuth required):

Quick Setup (Recommended)

1. Install dependencies:

# Using uv (recommended)
uv sync

# Or using pip (Windows users)
pip install --upgrade pip
pip install "mcp>=1.12.0" "anyio>=4.4.0" python-dotenv

2. Configure Claude Desktop (claude_desktop_config.json):

Windows (Recommended):

{
  "mcpServers": {
    "my-local-server": {
      "command": "cmd",
      "args": ["/c", "C:/path/to/your/project/run_local_simple.bat"],
      "cwd": "C:/path/to/your/project"
    }
  }
}

Linux/Mac:

{
  "mcpServers": {
    "my-local-server": {
      "command": "uv",
      "args": ["run", "python", "/path/to/your/project/server.py"],
      "env": {
        "LOCAL_MODE": "true"
      }
    }
  }
}

✅ Benefits: No OAuth setup required, immediate local development, stdio transport

Claude Code (Web Mode)

For production deployment, Claude Code natively supports SSE transport over HTTPS with OAuth 2.1 + PKCE:

# Add the server (OAuth flow will start automatically)
claude mcp add --transport sse my-server https://your-domain.com:8443/sse

When you connect, Claude Code will:

1. Discover OAuth server capabilities
2. Register itself as a dynamic client (RFC 7591)
3. Open your browser for Google authentication
4. Complete PKCE flow and store token securely

⚠️ Note: Browser access is required for authentication. This server does not support headless authentication.

Other MCP Clients

Configure your MCP client with:

• Transport: sse (Server-Sent Events)
• URL: https://your-domain.com:8443/sse
• Authentication: OAuth 2.0 with JWT tokens

Testing Your Server

# Test connectivity
curl https://your-domain.com:8443/sse

# Test OAuth metadata endpoint
curl https://your-domain.com:8443/.well-known/oauth-authorization-server

# After OAuth authentication, test with JWT token
curl -H "Authorization: Bearer your-jwt-token" https://your-domain.com:8443/sse

# Test specific tools (requires MCP client)
# Your MCP client will be able to call tools like:
# - add(5, 3) -> 8
# - secret_word() -> "OVPostWebExperts"
# - greeting://John -> "Hello, John!"

Architecture

Files Structure

├── server.py              # Main MCP server implementation (dual-mode support)
├── oauth.py               # OAuth 2.0 authentication implementation (web mode)
├── run_local.py           # Python script for LOCAL_MODE with version checking
├── run_local.bat          # Windows batch script with auto-install
├── run_local_simple.bat   # Simple Windows batch script (recommended)
├── requirements.txt       # Python dependencies for pip users
├── pyproject.toml         # Python dependencies and project config
├── .env                   # Environment configuration
├── .env.example           # Environment configuration template
├── Dockerfile             # Production container setup
└── scripts/
    ├── build.sh           # Docker build script
    ├── run-local.sh       # Local development script
    └── run-with-letsencrypt.sh  # Production deployment with SSL

Security Features

• OAuth 2.1 + PKCE: Enhanced security with Proof Key for Code Exchange
• Dynamic Client Registration: RFC 7591 compliant client registration
• HTTPS Enforcement: SSL/TLS encryption for all communications
• JWT Token Validation: Short-lived tokens (1 hour) for secure access
• Comprehensive OAuth Endpoints: Authorization server and protected resource metadata
• Input Validation: Type checking and parameter validation
• Error Handling: Secure error responses without information leakage
• Let's Encrypt Integration: Automatic SSL certificate management

Configuration Reference

Environment Variables

Variable	Description	Default	Required
SERVER_NAME	Name for the MCP server, Docker image, and container	mcp-template	No
LOCAL_MODE	Enable local mode: stdio transport, no OAuth, no HTTPS	false	No
GOOGLE_CLIENT_ID	Google OAuth Client ID	-	For web mode
GOOGLE_CLIENT_SECRET	Google OAuth Client Secret	-	For web mode
OAUTH_REDIRECT_URI	OAuth callback URL	-	For web mode
JWT_SECRET_KEY	Secret for JWT signing	-	For web mode
SSL_ENABLED	Enable HTTPS	false	No
DOMAIN_NAME	Your domain name	-	For HTTPS
SSL_CERT_PATH	SSL certificate path	-	If SSL enabled
SSL_KEY_PATH	SSL private key path	-	If SSL enabled
MCP_TRANSPORT	Transport protocol	sse	No
MCP_HOST	Host to bind to	0.0.0.0	No
MCP_PORT	Port to listen on	8443 (HTTPS) / 8899 (HTTP)	No

OAuth 2.1 + PKCE Configuration

Authentication uses OAuth 2.1 with PKCE for enhanced security. The server provides:

• Dynamic Client Registration (RFC 7591): Automatic client registration
• OAuth Authorization Server Metadata (RFC 8414): Endpoint discovery
• OAuth Protected Resource Metadata (RFC 8707): Resource server information
• PKCE Support (RFC 7636): Protection against code interception attacks

JWT tokens include:

• User's Google ID (sub)
• Email address
• Display name
• Profile picture URL
• Token expiration (1 hour)

Development

Local Development

# Install dev dependencies
uv sync --all-extras

# Run tests
uv run pytest

# Format code
uv run black server.py oauth.py

# Type checking
uv run mypy server.py oauth.py

# Lint code
uv run flake8 server.py oauth.py

Adding Custom Tools

1. Define your tool in server.py:

@mcp.tool()
def your_tool_name(param: str) -> str:
    """Tool description for AI agents"""
    # Implement your logic
    return "result"

2. Add authentication checks if needed:

@mcp.tool()
def protected_tool() -> str:
    """This tool requires authentication"""
    # Auth context is available in session_auth_contexts
    return "authenticated result"

3. Test your tool:

# Restart server to load changes
docker restart <your-server-name>

# Test via MCP client or direct HTTP calls

Production Deployment

Prerequisites

• Domain name pointing to your server
• Ports 80 (HTTP) and 8443 (HTTPS) open
• Docker installed

Deployment Steps

1. Configure DNS: Point your domain to your server's IP
2. Set environment variables: Domain, email, OAuth credentials
3. Run deployment script: ./scripts/run-with-letsencrypt.sh
4. Verify: Test HTTPS endpoint and authentication

Monitoring

Check server logs:

docker logs <your-server-name>

Monitor certificate renewal:

# Certificates auto-renew, but you can check status
docker exec <your-server-name> ls -la /etc/letsencrypt/live/

Troubleshooting

Common Issues

TypeError: 'function' object is not subscriptable (Windows/Claude Desktop)

• This error occurs with incompatible versions of anyio on Windows
• Solution (Recommended): Use the simple Windows batch script:

  {
    "mcpServers": {
      "my-local-server": {
        "command": "cmd",
        "args": ["/c", "C:/path/to/your/project/run_local_simple.bat"],
        "cwd": "C:/path/to/your/project"
      }
    }
  }

• Alternative: Manual package update:

  cd "your-project-directory"
  python -m pip install --upgrade pip
  python -m pip install --upgrade "mcp>=1.12.0" "anyio>=4.4.0" python-dotenv

• Ensure Python 3.10+ is installed
• On Windows, use forward slashes (/) in paths

SSL Certificate Errors

• Ensure domain points to your server IP
• Check firewall allows ports 80 and 8443
• Verify Let's Encrypt rate limits aren't exceeded

Authentication Failures

• Verify Google OAuth credentials are correct
• Check OAuth redirect URI matches configuration
• Ensure JWT token hasn't expired (1 hour lifetime)
• Verify Authorization: Bearer <jwt-token> header format

Connection Issues

• Verify Docker container is running: docker ps
• Check server logs: docker logs <your-server-name>
• Test basic connectivity: curl https://your-domain.com:8443/sse
• For Claude Desktop: Check the server runs without errors: LOCAL_MODE=true uv run python server.py

Getting Help

1. Check server logs for specific error messages
2. Verify environment variables are set correctly
3. Test each component (SSL, auth, MCP protocol) separately
4. Review the MCP specification at modelcontextprotocol.io

License

MIT License - see LICENSE file for details.

Contributing

1. Fork the repository
2. Create a feature branch
3. Make your changes
4. Add tests if applicable
5. Submit a pull request

This template provides a solid foundation for building production-ready MCP servers. Customize it according to your specific needs and use cases.

Mode Comparison

Feature	Local Mode (Claude Desktop)	Web Mode (Claude Code)
Transport	stdio	SSE over HTTPS
Authentication	None	OAuth 2.1 + PKCE
SSL/TLS	No	Yes
Client	Claude Desktop	Claude Code
Use Case	Local development	Production deployment
Setup Complexity	Minimal	Full OAuth setup required

Switch between modes by setting LOCAL_MODE=true (local) or LOCAL_MODE=false (web) in your environment.