alt Hacker NewsI always see the hard/complex criticism but find it confusing.. what is the perceived difficulty with MCP at the implementation level? (I do understand the criticism about exhausting tokens with tool-descriptions and stuff, but that's a different challenge)
Doesn't seem like implementation could be more simple. Just JSON-RPC and API stuff. For example the MCP hello-world with python and FastMCP is practically 1-to-1 with a http/web flavored hello-world in flask
There is a LOT under the surface. custom routes, bidirectional streaming choices (it started as a "local first" protocol). Implementing an endpoint from scratch is not easy, and the spec documentation moves very quickly, and generally doesn't have simple-to-digest updates for implementation.
I haven't looked in a few months, so my information might be a bit out of date, but at the time - if you wanted to use a python server from the modelcontextprotocol GitHub, fine. If you wanted to, say, build a proxy server in rust or golang, you were looking at a set of half-implemented server implementations targeting two-versions-old MCP specs while clients like claude obscure even which endpoints they use for discovery.
It's an immature spec, moderately complicated, and moving really quickly with only a few major 'subscribers' to the server side; I found it challenging to work with.