Thank you Dario for the heads-up. I just subscribed to the analytics list, so don't have the original mail to respond to.

<https://rest.wikimedia.org/en.wikipedia.org/v1/?doc#!/Page_content/page_title__get>
say
"List all pages." but the request produce only <1000 titles. There should
be other parameters like "limit=max" or something, shouldn't it?
How I can get ALL titles in one or multiple requests?
Where I can find documentation for this?

This end point is experimental at this point. There are several things we might want to change about it, so (as the documentation says), don't rely on it just yet. We have also consciously chosen not to expose paging yet, but have internal support for that already. See https://phabricator.wikimedia.org/T85640 for the hardening work on the paging token.

In the meantime, you can also get this information from the PHP API:

http://en.wikipedia.org/w/api.php?action=query&generator=allpages&gapfilterredir=nonredirects&gaplimit=500&prop=revisions&gapnamespace=0&format=json&gapcontinue=