With apologies for the late reply:
What you need really depends on the APIs in question, though. What @SnoopDougieDoug says was true once upon a time, but is rarely true (and I’ve never seen it effectively implemented) in the world of CRUD over HTTP, otherwise commonly known as REST (REST encompasses far more, and continues to develop, but most “RESTful” APIs are still at the CRUD over HTTP level). And these are the APIs that have been getting all the attention in recent years.
TL;DR: there’s no clean simple solution.
Read Bob Watson’s blog, and see whether his webinar is recorded (or maybe you caught it live – see his forum post).
Also, take a look at Tom Johnson’s material on his blog, http://idratherbewriting.com/, and hang out at your local API meetups. If you’re not familiar, start with APIs, not with docs. There’s a tremendous amount of interest in docs in the API community. Also, be prepared to move outside the world/s of FrameMaker and InDesign.