In the previous chapters, we successfully created an MCP Server. Now, we need to tell Cursor how to find and use this server. This is done through a configuration file.

Creating the Configuration File

1. First, open any project in Cursor (it can be a new project or an existing one).

2. Create a .cursor folder in the project root (if it doesn’t exist):

   mkdir .cursor

3. Create an mcp.json file in the .cursor folder:

   touch .cursor/mcp.json

4. Add the following configuration to the mcp.json file:

   {
       "mcpServers": {
           "about-me": {
               "command": "uv",
               "args": [
                   "--directory",
                   "/Users/{your_username}/Code/Playground/build_mcp_for_cursor/project",
                   "run",
                   "main.py"
               ]
           }
       }
   }

Understanding the Configuration

Let’s break down each part of this configuration file:

1. mcpServers

   • This is the main section that defines all MCP servers

2. about-me

   • This is our server name, which must match the name in FastMCP("about-me")
   • You can change this name, but ensure it matches in both places

3. command

   • Specifies which command to use to run the server
   • We’re using uv, our package manager

4. args

   • List of command arguments, including:
     • --directory: Specifies the project directory
     • Project path: You need to replace this with your actual project path
     • run: The uv run command
     • main.py: The Python file to run

Enabling the MCP Service

After creating the configuration file, we need to enable the service in Cursor:

1. Open Cursor Settings

   • Windows/Linux: Click the gear icon in the bottom left or use Ctrl + ,
   • macOS: Click the gear icon in the bottom left or use Cmd + ,

2. In the Settings panel:

   • Find and click “MCP” in the left sidebar
   • You should see our “about-me” service
   • Click the “Enabled” option to enable the service

Verifying the Service

Now we can test if our service is working:

1. Open Cursor’s Agent mode

   • Click the AI icon in the sidebar
   • Or use the keyboard shortcut to open the AI panel

2. Try these test questions:

   Q: What's my name?
   A: [AI will call get_user_name() and return "Lucas Lee"]
   
   Q: How old am I?
   A: [AI will call get_user_age() and return 30]

If you receive the correct answers, congratulations! Your MCP Server is configured and working properly!

Common Issues

1. Can’t Find MCP Settings?

   • Ensure your Cursor is up to date
   • Try restarting Cursor IDE

2. Service Appears Grayed Out?

   • Check if the configuration file format is correct
   • Ensure the project path is correct and accessible

3. Agent Can’t Get Information?

   • Make sure the service is properly enabled
   • Check if the Python service is running
   • Look at Cursor’s log information

Next Steps

Now that you’ve successfully configured and tested your MCP Server, you can:

• Add more custom tools
• Modify the returned information
• Implement more complex functionality
• Explore other possibilities with MCP servers