mcp-log-proxy

mcp-log-proxy

mcp-log-proxy can be used to see the messages to and from a MCP client and a MCP server using a Web interface.

Currently, it only supports the STDIO interface.

install

go install github.com/emicklei/mcp-log-proxy@latest

usage

mcp-log-proxy requires one argument -command that contains the full command line for starting the MCP server.

For example, to proxy traffic to the melrose-mcp server, the full command is:

mcp-log-proxy -command melrose-mcp

This example assumes that both tools are available on your execution PATH.

Once the proxy is started, messages can be viewed on http:/localhost:5656.

optional flags

You can override the Web page title using the title flag:

mcp-log-proxy -command melrose-mcp -title "Melrōse (proxy)"   

You can override the HTTP port(default 5656) using the port flag:

mcp-log-proxy -command melrose-mcp -port 9999

You can override the log file location of the proxy that captures errors in the proxy itself using the log flag:

mcp-log-proxy -command melrose-mcp -log /your/logs/mcp-log-proxy.log

Claude examples

This example proxies the use of the melrose-mcp server. Locate the binaries to get the correct paths.

"melrōse": {
  "command": "/Users/SOME-USER/go/bin/mcp-log-proxy",
  "args": [
    "-command",
    "/Users/SOME-USER/go/bin/melrose-mcp -log /Users/SOME-USER/Library/Logs/claude-melrose.log",
    "-log",
    "/Users/SOME-USER/Library/Logs/claude-melrose-proxy.log",
    "-port",
    "7788",
    "-title",
    "Claude Melrose MCP"
  ]
},

Proxying the browsermcp server.

"browsermcp": {
  "command": "/Users/SOME-USER/go/bin/mcp-log-proxy",
  "args": [
    "-command",
    "npx @browsermcp/mcp@latest",
    "-log",
    "/Users/SOME-USER/Library/Logs/claude-browsermcp-proxy.log",
    "-port",
    "7799",
    "-title",
    "Claude Browser MCP"
  ]
}

Goose Example

This example proxies the use of the melrose-mcp server. Locate the binaries to get the correct paths.

/Users/SOME-USER/go/bin/mcp-log-proxy -command /Users/SOME-USER/go/bin/melrose-mcp -log /Users/SOME-USER/Library/Logs/goose-melrose.log -port 8888 -title Melrose-MCP

Error information

Multiple proxies

All running mcp-log-proxy processes will register themselves in .mcp-log-proxy-instances.json located in your home directory.

© 2025, https://ernestmicklei.com. MIT License.