ReaScript API
From CockosWiki
ReaScript API Documentation
Don't forget - Call API functions using RPR_functionname() - Don't forget the RPR_
Functions that cannot return information in the parameter list will return a single value, functions that can return information in the parameter list will return a list of values.
Anything in the API documentation that is marked with a '?' is an assumption or something I'm just not sure about. If you happen to know whatever it is for certain - please correct or confirm the entry.
Anything you see that's wrong or incomplete - and there's certainly plenty incomplete - please add a brief note saying what needs to be done. Someone will be along in a while with the time to make the change look good if you don't have the time.