My dream was for MCP to allow services like ours (cybersecurity) to provide a self documenting endpoint with authentication, and we just give users a URL and it just frikkin works. Instead from day 1 it’s been multiple standards as they pivoted, a context hungry feature, and feels like a kludge. That burned the idea of MCP for me and I’ve had such success with local tools and APIs that it’ll take a lot for me to go back.
I mean… so just HTTP + OpenAPI spec?
It actually doesn’t matter. Pick your favorite way of giving a dev access to capability on a remote server.
Plus You're likely building an API already if you have an MCP. Not everyone using MCP is a dev, we have random corporate workers using our MCP. They don't know what an API is but they can add a plugin from an agent marketplace (which can also contain skills) and MCP is a bit narrower with a clear authorization system, tool discovery, and annotations (agents ask "confirm you want you want to write this").
Just give your end-users flexible options. If they have Claude Code then build more around the API side if needed.