Simple MCP Server and Client Demo from FastMCP

This is just followed the demo from FastMCP. However adding few tips to run in your local system may helpful.

Steps

• install FastMCP
• Run pip install -r requiremetns.txt
• Update or create the .env file with ANTHROPIC_API_KEY=your-api-key-goes-here
• run server by python my_server.py in one terminal
• run client by python my_client.py or python my_adv_client.py in another terminal

If you try to run server by python my_server.py it will start in the server starts using stdio (Standard Input/Output). In this case you can't run client by python my_client.py because it will not able to find the server.

Information

The Communication Flow:

User/LLM Request: The LLM decides it needs a tool (e.g., "Check the weather" or "Query a database").

Client Call: Your Client (my_client.py) receives this request and calls the specific tool on the MCP Server.

Server Execution: The MCP Server runs the local code, fetches the data, and sends the result back to the Client.

Client Forwarding: The Client takes that raw data and sends it to the LLM as context.

Final Output: The LLM uses that context to give you a human-readable answer.

Key Distinction:

The Server never talks to the LLM directly. It is "blind" to the LLM.

The Client (your app) manages the security, the connection, and the conversation flow.

Continue develop this application in future

Thanks for your support