The extract annotations driver is a command line interface to extracting annotations from a source tree. It's similar to the gradle ExtractAnnotations task, but usable from the command line and outside Gradle, for example to extract annotations from the Android framework itself (which is not built with Gradle). It also allows other options only interesting for extracting platform annotations, such as filtering all APIs and constants through an API white-list (such that we for example can pull annotations from the master branch which has the latest metadata, but only expose APIs that are actually in a released platform), as well as translating android.annotation annotations into android.support.annotations.