nest thermostat API

Hi. Has anyone looked into the new API for nest thermostats.I'm in desperate need for a nest thermostat plugin.Thank

I haven't looked recently. When I looked initially, it was not planned to be public. It was only going to be released to limited vendors.

https://developers.nest.com/reference/api-thermostat

You linked the old deprecated (discontinued) Nest thermostat API. To be precise, this API is in "maintenance mode" and (afaik) is only for users who still have non-migrated Nest accounts.

The replacement for the old Works With Nest program is Works With Google Assistant. There is a new Smart Device Management (SDM) API as part of that program. There is apparently a way (with registration) to gain limited access to that API through "sandbox" access which it seems Google intends only as a way to "evaluate the API or create personal use integrations." To go beyond sandbox access, and do things like developing an Indigo plugin would seem to require that you become certified by Google as a partner/developer. The examples of such partnerships they show are companies like Control4, Dish, and Vivint. Perhaps Indigodomo could form such a partnership and develop a plugin?

Some things that would be good to know:
What does it take for a developer to gain full access to the SDM API to develop either an update to Nest Home or a replacement?
Would "sandbox access" be adequate to develop an Indigo plugin?
Why are Nest Protect (smoke detectors) apparently not included among the initial device types in the API demo?