> My air conditioner just died, would be great if a matter compatible one became available.

What would you want the API to look like here?

I would be very conservative about opening up an API if I was a manufacturer. The reason being that there may be misuses by amateur coders that may increase wear on the product, and leading to increase in warranty claims.

I, as a manufacturer, would much rather prefer customers buy something like a Nest/Ecobee, etc. and manage that. Nest (and likely Ecobee) likely have smarts to not turn the AC on/off 30 times within 10 minutes, etc. Also, you benefit from other algorithms like "Time-to-Temp" (Nest), malfunctioning equipment alerts (Nest), etc. If you're in the US, many electricity utilities will give you a discount if you buy a smart thermostat, and then you can further gain $$ by enrolling in demand-response programs.