There are several properties in the appendix that have no description. This generally seems to be because they use @NestedConfigurationProperty to refer to a type in another module. With this arrangement, the source of the nested configuration property class is not available so the description cannot be harvested from the javadoc. This is a known problem that we're not sure how to solve. Until we're able to come up with a solution, we can continue to rely on additional metadata instead. To help to avoid the problem happening again, perhaps we can fail the build if a property has no description.
Comment From: weixsun
I also noticed this issue and I always feel like a little thing is off, but I don't know where it is
Comment From: wilkinsona
Working on this has shown that the problem tackled by #28075 occurs more frequently than I'd realised during local builds. With something in place to check that all properties have descriptions, the problem sometimes causes local build failures. The build passes if full compilation is forced, for example by deleting build/classes, and sometimes also requires --no-build-cache if the local cache has been polluted with incomplete metadata.
Comment From: wilkinsona