I had the same frustration and wanted to see "under the hood", so I coded up this little agent tool to play with MCP (sse and stdio), https://github.com/sunpaze

I had the same frustration and wanted to see "under the hood", so I coded up this little agent tool to play with MCP (sse and stdio), https://github.com/sunpazed/agent-mcp https://github.com/sunpazed/agent-mcp I really is just json-rpc 2.0 under the hood, either piped to stdio or POSTed over http.