If you don't need to write resolvers by hand, from experience I can tell you writing an OpenAPI over an ORM/ODM is trivial and will accomplish the same end. It's schema-first and quick and simple (it's as simple as defining the schema in your ORM library, your generator will handle the rest)
If you do need them, as you said it's going to be complex either way.
I essentially only do that for mutations, and they are no more complex than writing POST handlers.
Essentially all the rest is schema-first and it's _so_ quick and simple.
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