Only to share this news on
Google Assistant Project
It bases on
https://developers.google.com/assistant/sdk/overview :
The Google Assistant SDK lets you add hotword detection, voice control, natural language understanding and Google’s smarts to your devices. Your device captures an utterance (a spoken audio request, such as What's on my calendar?), sends it to the Google Assistant, and receives a spoken audio response in addition to the raw text of the utterance.
Looking at the SDK, there're examples with Python and several Code languages (like Java) but all through
Google Assistant gRPC API.
With B4J, we could execute the python program example (not tested) but should be great to access gPRC API (with a wrapper or JavaObject if possible) from B4J on rPI and use GPIO/Wiring Pi to customize the solution.