What are the services of automatic answers to user questions?

Question

API

What web services exist for which you register, and is it possible to send them via API, for example, questions, and based on their data (or the data that the moderator entered for them), they send an answer to the question asked?
It seems that I heard that bootstrap (?) has such a service, roughly speaking there is a list of all incoming questions and they can be answered directly from their website, and it will already send a response to the desired resource via the REST api.
Tell me the names of the resources that contain something like this functionality
Thank you