could not start server

[ProdSec-Albert]

When I run this from the Claude desktop, I’m able to connect to the MCP Server and everything works fine.
But as soon as I run uvx mcp-scan@latest I get the following error. I’d appreciate help understanding what might be causing it.

uvx mcp-scan@latest
Installed 76 packages in 141ms
Invariant MCP-scan v0.3.4

● Scanning ~/.codeium/windsurf/mcp_config.json file does not exist

● Scanning ~/.cursor/mcp.json file does not exist

● Scanning ~/Library/Application Support/Claude/claude_desktop_config.json found 1 server
│
└── MYorgname could not start server

● Scanning ~/.vscode/mcp.json file does not exist

● Scanning ~/Library/Application Support/Code/User/settings.json file

[mmilanta]

Thanks for pointing this out,
I suspect the server is misconfigured. Is the server working when using it in the Claude app? If so, could you share the config file?
Thanks

[ProdSec-Albert]

Yes, the server is working when I use the Claude app

"mcpServers": { "MYorgname": { "command": "npx", "args": [ "-y", "@MYorgname/mcp-server" ], "type": "stdio", "env": { "ORG_API_KEY": "XX-XX-XX-X-XX", "ORG_PRIVATE_KEY_PATH": "/Users/gogi/secret.key", "ENABLE_WRITE_OPERATIONS": "false", "ORG_API_BASE_URL": "https://api.org.io/v1" } } } }

[lbeurerkellner]

I encountered a similar issue with context8:

"context7": {
    "url": "https://mcp.context7.com/mcp",
    "headers": {}
  }

[woodlyer]

I meat the same problem.

#### mcp.json 
{
        "servers": {
                "my-mcp-server-github": {
                        "url": "https://api.githubcopilot.com/mcp/",
                        "type": "http"
                },
                "special-add-server": {
                        "url": "http://localhost:8000/mcp/",
                        "type": "http"
                }
        },
        "inputs": []
}

I have to mcp server.
One is github mcp server.
The other one is designed by myself. special-add-server.

The result is this.
my-mcp-server-github could not start server.
**this server is provided by github. **

● Scanning .vscode/mcp.json found 2 servers
│
├── my-mcp-server-github could not start server
└── special-add-server
    ├── prompt     ask_about_topic           ✅
    ├── resource   get_greeting              ✅
    ├── resource   get_config                ✅
    ├── resource   read_log                  ✅
    ├── tool       greet                     ✅
    ├── tool       add                       ✅
    ├── tool       special_add               ✅
    ├── tool       special_multi             ✅
    └── tool       md5sum                    ✅

---

by using --verbose, I find there is no Auth header. Connect to github failed.

 HTTP Request: POST https://api.githubcopilot.com/mcp/ "HTTP/1.1 401 Unauthorized"

Maybe you can also add --verbose to see what the problem is.

[gaochen61]

How to reduce the number of entities? I tried to test Github mcp server using MCP-Scan and the result was that the configuration had too many entities.

I tried to add some tools to whitelist, but the number of entities didn't change.

[acn-masatadakurihara]

The same issue occurred with a homemade stdio MCP server. It was resolved by disabling console.log() output from the MCP server.
It seems that mcp-scan fails the handshake if the MCP server is emitting logs at startup.