As mentioned in IntelliJ IDEA’s 2025.2 release:
https://www.jetbrains.com/idea/whatsnew/#page__content-jspecify-support--a-major-step-toward-safer-code
IntelliJ, Kotlin, and other tools already recognize and respect these annotations.
As far as I know (I'm using Quarkus), currently only jakarta.validation annotations are considered when generating the OpenAPI document — including for nullability, constraints, etc.
However, jakarta.validation annotations are intended for validating method input parameters:
They are suitable for annotating POST/PUT request payloads.
They are not suitable for annotating return types — for example, the return type of a REST endpoint.
It would be helpful if SmallRye OpenAPI could support JSpecify-style nullability annotations (@nullable, @nonnull, @NullMarked, @NullUnmarked) for better schema generation and more accurate documentation of REST APIs.
Or should I use kotlin instead? 😅