Currently the only official API I could find is this one. It doesn’t say anything about posting and it’s calling threads “entries” (I assume it was renamed before I got here).
If I want to develop an app for kbin today and I don’t want to learn how to scrap the website, what API docs should I follow?
As far as I know there are no clients that support it but a lot of the smaller AP services do support the C2S. The masto API is only the de facto standard as long as each project chooses to support it. Kbin doesn’t have an API yet, so this is the best time to make the decision.
EDIT: There is a ton of demand for a kbin app so if kbin goes with the C2S over the masto API, that will drive creation of C2S apps.