Homey/Athom is responsible for forwarding your devices to Google Home.
I.e. they recently added blinds. There was nothing the developers had to do.
Temp sensors (and open/closed) aren’t being forwarded by Athom.
Thermostats, however, are.
You could create an virtual thermostat to have them in Google Home. If you don’t want that there is nothing you can do other than bugging Athom to have them add sensors.
P.s. here is a full list of Gooogle Home supported device traits:
And device types:
I’d like to have more devices added to Google Home:
- Air conditioner
- Garage Door