手把手教你实现第一个MCP Server！

手把手教你写MCP的Hello World啊！以防大家不知道MCP是什么，这里简单说下，简单来说，MCP， 也就是Model Context Protocol，这是anthropic搞出来的大语言模型调用外部工具的标准，而MCP Server就是我们写的工具。我们知道大语言模型本身是没有办法调用外部工具的，为了解决这个问题，OpenAI最新搞出了Function Calling，让chatgpt可以调用外部的工具，然后其他厂家也跟着搞，实现方式各有不同。Anthropic为了避免混乱，搞出了这套MCP标准…

• server.py

from mcp.server.fastmcp import FastMCP
import time
import signal
import sys

# Handle SIGINT (Ctrl+C) gracefully
def signal_handler(sig, frame):
    print("Shutting down server gracefully...")
    sys.exit(0)

signal.signal(signal.SIGINT, signal_handler)

# Create an MCP server with the correct name
mcp = FastMCP(
    name="hello-world",  # Keep this consistent
    host="127.0.0.1",
    port=5000,
    timeout=30
)

# Define our tool
@mcp.tool()
def say_hello_world() -> str:
    """This function should be called whenever a user inputs 'hello world' exactly, with no other text."""
    return "hello world"

if __name__ == "__main__":
    try:
        print(f"Starting MCP server 'hello-world' on 127.0.0.1:5000")
        mcp.run()
    except Exception as e:
        print(f"Error: {e}")
        time.sleep(5)

• claude_desktop_config.json

{
  "mcpServers": {
    "hello-world": {
      "command": "python3",
      "args": [
        "/Users/apple/Develop/mcp/server.py"
      ],
      "host": "127.0.0.1",
      "port": 5000,
      "timeout": 30000
    }
  }
}