We have been trying to fix errors related to our swagger documentation and upgrading it to the latest versions of openapi (or there about) and the pull requests for that are already in place.
For this GSoC i would suggest on top of the work on going, we work towards having a tooling or coming up with one that either autogenerates our swagger document by looking at the javadocs, return types, etc. Part of the work that autogenerates our swagger documentation i have been working on just uses reflection to scan through openmrs resource handlers. Maybe we can build on top of that for the tooling we envision? The ideal is to have an openapi spec generated at compile time rather than runtime like it is at the moment to curb any errors at compile time rather than waiting to see errors or not at runtime.
For reference,