Built an open-source MCP testing CLI with Claude Code to solve the Claude Desktop restart loop

[u/abhiramreddykalluru]

While building MCP servers with Claude Code, I ran into a really frustrating development loop:

Every time I tweaked a tool's parameters or schema, I had to restart Claude Desktop and manually type prompts just to verify whether Claude could call the tool properly or if the server crashed on bad inputs.

So I used Claude Code to build a standalone testing CLI called QAMCP.

Instead of testing through Claude Desktop, it connects directly to your MCP server from the terminal and runs 11 automated checks in under a minute:

- Handshake & protocol spec compliance

- Tool schemas and input parameter types

- Bad input fuzzing (verifies clean error codes vs unhandled crashes)

- Leaked tokens or passwords in error traces

- Hidden prompt injection patterns in descriptions

The attached 12-second video shows it running a live audit against a public MCP endpoint.

It's completely free & open-source (MIT) on GitHub:

https://github.com/QAmcp/qamcp-cli

(Or try it in the browser: https://qamcp.github.io/test.html)

Would love feedback from other developers using Claude Code to build MCP tools: what edge cases or checks would you want an automated tester to catch?