https://blog.dialogflow.com/post/build-for-google-assistant/
https://dialogflow.com/docs/concepts/slot-filling#top_of_page
This conversation playground allows you to explore constructing a response that adheres to the Actions on Google API.
https://developers.google.com/actions/conversation-api-playground
fulfillment in js - nice tutorial
https://www.youtube.com/watch?v=biN00SoMRI8
https://www.youtube.com/watch?v=yFyNouueu2g
very good video sample
C# sample - Your First Chatbot using Microsoft’s Bot Framework and Dialogflow API
very good audio sample
Advanced sample :