Field help is your friend! Help > Field Help. Look for the technical information at the bottom of the field help screen.
I believe the proper SDK is locked up behind a hefty paywall. The documents on EpicWeb are the best you have access to. Check out Documentation > Technical Reference Guides, and > User Guides. Don’t get your hopes up. At least REST is in there. I suggest:
BPM Cookbook, REST services, ICE Tools User Guide, and Customization User Guide to start with.
Just reach out to the community. We all know how frustrating it is to not have great documentation.
Good luck!
While I’m over here also giggling, I will also try to be helpful…
There is some technical documentation, hopefully you have been given access to a site called EpicWeb, or if you don’t someone can download the documents for you.
In EpicWeb, you’ll be looking for Kinetic Documentation → Technical Reference Guides.
There is one specifically about REST Services.
There is another called BPM Cookbook.
EDIT: I scrolled back up and I see that @NateS already provided this answer. Thanks Nate.