What is difference between Applications and APIs? What do we use APIs?

[ty.frith]

Hey there @rdruzhkov! I apologize for the delayed response on this one, but wanted to get back to you nonetheless.

@rdruzhkov

So the main goal of having an API is to create audience value that will allow to the backend/API to understand if the id_token, access_token etc are intended to be used by the backend/API. Am I right?

That is exactly right.

@rdruzhkov

If I’m right then why can’t we use application client_id as audience? I know that my backend/API is going to be used by the application. So it seems to me that on the backend/API side I can validate audience by checking if it’s equal to application client_id, since my application is allowed to interact with backend/API.

You might be able to use the client_id as the audience as it’s just an identifier although I cannot confirm there won’t be any issues with this approach and don’t recommend