Yes it is your responsibility to take care of transitive dependencies. See the following blog post for more details
Hope that helps
You are correct that .jar files need to be in the userlib folder.
What compilation error message are you seeing?
I’ve added dependency to Firebase Messaging with its dependencies.
To test it, I added an import line in one of my Java actions.
And I get this error:
error: package com.google.firebase.messaging does not exist
After placing the jar files in userlib folder, try opening the project using eclipse and include the jar files in the project if you don’t see as included.