When I use Perplexity to look up a research topic, I sometimes see a paper cited even though the full text is behind a publisher paywall. Does its academic search results coverage draw on the full paper, or mainly on the abstract and other publicly available material?

I’m trying to judge how much confidence to put in a summary when I can’t open the source itself. If you’ve compared Perplexity’s summaries with papers you can access, I’d be interested to hear what it gets right—and where the coverage seems thin.