mcpspy.dev

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The website and documentation for mcp-spy — browser devtools, but for AI tool calls.

mcp-spy is a free & open-source observability proxy for the Model Context Protocol. It sits between your AI client (Claude Desktop, Cursor, Windsurf…) and any MCP server, and shows every JSON-RPC message — request, response, duration, status — live in a terminal UI.

The CLI is published on npm as mcp-spy:

npx mcp-spy

No account. No cloud. No telemetry. Logs live in a local SQLite database on your machine.

This repo

This repository contains the mcpspy.dev website: a static landing page and the full documentation, built with Next.js and Tailwind CSS. It shares its paper-and-ink, ASCII-art design language with gabsalvo.com and domoroshi.tech.

Develop

npm install
npm run dev

Open http://localhost:3000.

Build

npm run build

Deployed on Vercel — every push to main redeploys automatically.

Contributing

Found a bug or a typo? Open an issue. Want a feature? PRs welcome.

License

MIT © Gabriele Salvo