JSON API fields format / results' titles not showing

[Camilo Bravo]

I'm trying the JSON API on a Blacklight installation, and the records don't seem to have titles. Also, the "machine name" for some fields seem different from the documentation, for example "author_tsim" vs "author_person_display_ssm" in this URL:

https://catalog.libraries.psu.edu/catalog.json?utf8=%E2%9C%93&search_field=all_fields&q=whale

I also tried looking at the "single record" endpoint (for the first result in the link above, it's this). It contains different fields from the search endpoint, but still no title.

Can I maybe use query string params to select which fields I want to see in the results? And, is there a standardized list of field names? (I'm thinking maybe the API docs are out of date and the ones from psu.edu are the real ones).

Thanks in advance,

Camilo