MCP Log Proxy

1## mcp-log-proxy
2[![Trust Score](https://archestra.ai/mcp-catalog/api/badge/quality/emicklei/mcp-log-proxy)](https://archestra.ai/mcp-catalog/emicklei__mcp-log-proxy)
3 
4`mcp-log-proxy` can be used to see the messages to and from a MCP client and a MCP server using a Web interface.
5 
6Currently, it only supports the STDIO interface.
7 
8![web log view](doc/screenshot2.png)
9 
10### Multiple proxies
11 
12![multi flow](doc/multiple_proxies.png)
13 
14All running mcp-log-proxy processes will register themselves in `.mcp-log-proxy-instances.json` located in your home directory. On the web page, you can use the selector to switch to another proxy instance.
15 
16## install
17```shell
18brew tap "emicklei/tap"
19```
20 
21and then
22 
23```shell
24brew install emicklei/tap/mcp-log-proxy
25```
26 
27or via Go
28 
29```shell
30go install github.com/emicklei/mcp-log-proxy@latest
31```
32 
33### usage
34 
35`mcp-log-proxy` requires one argument `-command` that contains the full command line for starting the MCP server.
36 
37For example, to proxy traffic to the `melrose-mcp` server, the full command is:
38 
39    mcp-log-proxy -command melrose-mcp
40 
41This example assumes that both tools are available on your execution PATH.
42 
43Once the proxy is started, messages can be viewed on `http:/localhost:5656`.
44 
45#### optional flags
46 
47You can override the Web page title using the `title` flag:
48 
49    mcp-log-proxy -command melrose-mcp -title "Melrōse (proxy)"   
50 
51You can override the HTTP port(default 5656) using the `port` flag:
52 
53    mcp-log-proxy -command melrose-mcp -port 9999
54 
55When running multiple proxies, the `mcp-log-proxy` will detect whether a HTTP port is taken and choose a different port instead. Using the Web UI you can select any of the other running proxies.
56 
57You can override the log file location of the proxy that captures errors in the proxy itself using the `log` flag:
58 
59    mcp-log-proxy -command melrose-mcp -log /your/logs/mcp-log-proxy.log
60 
61### Claude examples
62 
63This example proxies the use of the `melrose-mcp` server.
64Locate the binaries to get the correct paths.
65 
66    "melrōse": {
67      "command": "/Users/SOME-USER/go/bin/mcp-log-proxy",
68      "args": [
69        "-command",
70        "/Users/SOME-USER/go/bin/melrose-mcp -log /Users/SOME-USER/Library/Logs/claude-melrose.log",
71        "-log",
72        "/Users/SOME-USER/Library/Logs/claude-melrose-proxy.log",
73        "-port",
74        "7788",
75        "-title",
76        "Claude Melrose MCP"
77      ]
78    },
79 
80Proxying the `browsermcp` server.
81 
82    "browsermcp": {
83      "command": "/Users/SOME-USER/go/bin/mcp-log-proxy",
84      "args": [
85        "-command",
86        "npx @browsermcp/mcp@latest",
87        "-log",
88        "/Users/SOME-USER/Library/Logs/claude-browsermcp-proxy.log",
89        "-port",
90        "7799",
91        "-title",
92        "Claude Browser MCP"
93      ]
94    }
95 
96### Goose Example
97 
98This example proxies the use of the `melrose-mcp` server.
99Locate the binaries to get the correct paths.
100```
101/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
102```
103 
104### Error information
105 
106![web log view](doc/screenshot1.png)
107 
108© 2025, https://ernestmicklei.com. MIT License.
109