The Oracle page "How to Write Doc Comments for the Javadoc Tool" has a link to a "Empty Template for Package-Level Doc Comment File" which does not show the expected content of a basic 'package.html' file. I am maintaining old Javadoc and it would be interesting to see a correct example of package.html and overview.html.
Is there a getting started with (classic) Javadoc page which shows the correct content of these files?
I think the answer you want is here.
The new package-info.java is a better way do document a package.