Which online consultant platform has a rich API?

Question

API

I choose a platform for online operators. The main requirement is an API for communication with users, i.e. in order to publish messages from the user through the API, and receive responses from the platform and deliver them to the user on their own.
Livetex (messaging api) has this, but they have other weaknesses.
What else do you have?

Answer 1

I settled on omnidesk, implemented everything I planned.