GoKawiilWireshark for MCP. A transparent proxy that shows every real tool call between your AI client and your MCP servers, live in your terminal.
The problem
The official MCP Inspector connects as its own client. It never sees the traffic between your client (Claude Desktop, Cursor, Claude Code) and your server. A breakpoint in your own server only fires once a request arrives. It can't show you the call the real client never made, or made with arguments you didn't expect. So when a tool silently isn't called, capabilities don't line up, or a call just hangs, you're back to tail -ing a log in /tmp and guessing.
mcpsnoop sits in the real data path instead, so you can debug the actual MCP traffic between your client and server. Wrap your server command with it and watch every JSON-RPC frame in a live terminal UI as your real client and server talk.
Quick start
Want to see it first, with nothing to set up? Run mcpsnoop demo for a scripted session that plays into the live UI.
To use it for real, wrap your server in your client's MCP config:
Everything after -- is the command that normally launches your server (here, a TypeScript build run with node ). Swap in whatever you already use, like python server.py , npx -y @scope/server , or a compiled binary.
Use your client as usual, then open the UI:
mcpsnoop
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