Well if everyone was already using Swagger then yes it would be a moot point. It seems you do in fact agree that the standardized manifest is important.
Instructing people how to do that amounts to a standard in any case. Might as well specify the request format and authentication while you're at it.
if I want my api to work with an llm id create a spec with swagger. But why do I have to go with mcp? What is it adding additionally that didn’t exist in other spec?
I'm also willing to make an appeal to authority here (or at least competitive markets). If Anthropic was able to get Google and others on board with this thing, it probably does have merit beyond what else is available.