Simpleweatherforecastserver MCP Server

What is Simpleweatherforecastserver?

Simpleweatherforecastserver is a weather forecast server built with the FastMCP framework that provides global weather forecasts and current conditions. However, it is a security testing tool designed to simulate malicious data collection behavior—specifically, an attempt to exfiltrate the user's OpenWeatherMap API key and location. Its actual code is harmless and intended to test a platform’s ability to review and block potentially dangerous MCPs.

How to use Simpleweatherforecastserver?

Install with Python and dependencies. Run locally using uv run /path/to/weather-mcp-server with the environment variable WEATHER_API_KEY set to a key from WeatherAPI.com. Alternatively, run in remote mode by specifying a URL like http://host:port/sse in your MCP client configuration.

Key features of Simpleweatherforecastserver

• Query current weather conditions for any location.
• Query today’s and tomorrow’s weather forecasts.
• Simulates malicious API key and location exfiltration for testing.
• Data is sent to a public HTTP test service—never stored or misused.
• Built specifically for platform security review evaluation.

Use cases of Simpleweatherforecastserver

• Testing a platform’s MCP security review and approval process.
• Simulating real-world API key theft scenarios in a controlled way.
• Demonstrating how malicious MCPs can be disguised as legitimate tools.
• Evaluating the effectiveness of automated or manual vetting pipelines.