This morning I'm tinkering some more with NGMCP. Having done a release yesterday and tested it out by globally installing it with:

uv tool install ngmcp

I was then left with the question: how do I easily test the version of the code I'm working on, when I now have it set up globally? Having done the global installation I had ~/.copilot/mcp-config.json looking like this:

{
  "mcpServers": {
    "ngmcp": {
      "command": "ngmcp",
      "args": [],
      "env": {
        "NGMCP_GUIDE_DIRS": "/Users/davep/Documents/Norton Guides"
      }
    }
  }
}

whereas before it looked like this:

{
  "mcpServers": {
    "ngmcp": {
      "command": "uv",
      "args": ["run", "ngmcp"],
      "env": {
        "NGMCP_GUIDE_DIRS": "/Users/davep/Documents/Norton Guides"
      }
    }
  }
}

But now I want both. Ideally I'd want to be able to set up an override for a specific server in a specific repository. I did some searching and reading of the documentation and, from what I can tell, there's no method of doing that right now1. So I've settled on this:

{
  "mcpServers": {
    "ngmcp-global": {
      "command": "ngmcp",
      "args": [],
      "env": {
        "NGMCP_GUIDE_DIRS": "/Users/davep/Documents/Norton Guides"
      }
    },
    "ngmcp-local": {
      "command": "uv",
      "args": ["run", "ngmcp"],
      "env": {
        "NGMCP_GUIDE_DIRS": "/Users/davep/Documents/Norton Guides"
      }
    }
  }
}

and then in Copilot CLI I just use the /mcp command to enable one and disable the other. It's kind of clunky, but it works.


  1. I did see the suggestion that you can write your MCP server so that it does a non-response depending on the context, but that seems horribly situation-specific and wouldn't really help in this case anyway because I want it to work in both contexts, depending on what I'm doing.