Hi all, OpenAPI (https://github.com/zweidenker/OpenAPI) got the same treatment as JSONSchema recently: the baseline dropped its stale 2020-era JSONSchema pin and now tracks JSONSchema's master, and the library actually validates whole documents now instead of just parsing them. What's new: OADocumentValidator checks a full document against the official OAI 3.0 meta-schema (bundled, Apache-2.0), with real error messages, not just true/false. Verified against six real OpenAPI 3.0 documents from the official spec repo (petstore, petstore-expanded, api-with-examples, callback-example, link-example, uspto) - round-tripping them surfaced and fixed several real bugs that hand-written test documents never would have. OpenAPI-Client was exercised against a real spec (Stripe's) end-to-end, which is what it took to find that request bodies were JSON-only when most real APIs use form-urlencoded bodies. That's fixed too. Scope is still explicitly OpenAPI 3.0. 3.1/3.2 use a different schema dialect (JSON Schema 2020-12 + OAS vocabulary - $dynamicRef, $ref-with-siblings, unevaluated*), which needs machinery JSONSchema doesn't have yet. Not pursuing that for now is a deliberate decision, not an oversight. Code and README (installation, quick start, what's not supported) are on GitHub: https://github.com/zweidenker/OpenAPI Norbert