I think the main problem is that the source GP is using, https://github.com/firebase/firebase-admin-java, contained almost nothing that context7 extracted as "docs".

It looks like https://firebase.google.com/docs/ is being refreshed as I type this, I imagine that using that as a source and including "Java" in the topic filter might give more results (or maybe the https://github.com/firebase/firebase-docs has the same content).