FastMCP Calculator Server

A Model Context Protocol (MCP) server providing calculator functionality with authentication options.

Quick Start

1. Install Dependencies

pip install -r requirements.txt

2. Choose Authentication Mode

No Authentication (Port 8000)

python calculator_server.py

JWT Authentication (Port 8001)

python calculator_server_auth.py
# Copy the bearer token from output

Google OAuth (Port 8002)

# Setup: Get credentials from https://console.cloud.google.com/
# Create .env file with GOOGLE_CLIENT_ID and GOOGLE_CLIENT_SECRET
python calculator_server_google_oauth.py

Calculator Tools

• add(a, b) - Add two numbers
• subtract(a, b) - Subtract numbers
• multiply(a, b) - Multiply numbers
• divide(a, b) - Divide numbers
• power(base, exponent) - Raise to power
• modulo(a, b) - Get remainder
• square_root(n) - Calculate square root
• evaluate_expression(expr) - Evaluate math expression
• calculate_percentage(value, pct) - Calculate percentage
• average(numbers) - Calculate average

Google OAuth Setup

1. Go to https://console.cloud.google.com/
2. Create OAuth 2.0 Client ID
3. Add redirect URI: http://localhost:8000/auth/callback
4. Copy credentials to .env:

GOOGLE_CLIENT_ID=your-id.apps.googleusercontent.com
GOOGLE_CLIENT_SECRET=your-secret
SERVER_BASE_URL=http://localhost:8000

Claude Desktop Setup

Edit your Claude config file:

Windows: %APPDATA%\Claude\claude_desktop_config.json macOS: ~/Library/Application Support/Claude/claude_desktop_config.json

{
  "mcpServers": {
    "calculator": {
      "command": "python",
      "args": ["path/to/calculator_server.py"]
    }
  }
}

Production

• Use HTTPS (required for Google OAuth)
• Store credentials securely
• Enable rate limiting
• Set up monitoring

Resources

• FastMCP Documentation
• MCP Specification