[handrews]

Part of the problem is that OpenAPI depends on JSON Schema and JSON Schema is a runtime constraint system, not a data definition system [1]. That shows up in the diagram with the three colors crammed into the "Interface Modeling and Validation" area because the boundary between those three ends up being very weird. And there's no standard for using JSON Schema as a data definition system... people just started kinda doing stuff.

I've been advocating for finding a better data definition system for Moonwalk (and yes, that's my name on the post-2016 JSON Schema drafts- it's a great runtime constraint system, and it could still be useful for that purpose alongside a system more tailored to data definition).

[1] https://modern-json-schema.com/json-schema-is-a-constraint-s...