Yup exactly. My tool is supposed to sit between MCP clients and servers. For now only stdio is in scope. Your tool is great. An MCP server for LSPs! I'll be taking it for a spin.
One advantage of MCP being "inspired by" LSP, at least to people like myself who work on LSP tools, is that a decent chunk of existing LSP code can be reused and repurposed. For example, most editors already ship with code for managing local server sidecars over stdio. There are a few annoying differences though like the lack of a header section in MCP.