WebAPI: why does it use MVC namespace and classes?

Hello,

I'm pretty new to the WebAPI world.

So far I've read some great articles on how to create and call WebAPI; however, I'm still a bit puzzled about one thing: even if we create "just" a WebAPI, not a MVC application, we are almost "stuck" with theMicrosoft.AspNetCore.Mvc namespace.

For instance:

• ControllerBase is part of the namespace;
• HttpMethodAttribute (HttpGet, HttpPost, etc.) is part of the namespace;
• even return methods like Ok(), CreatedAtRoute(), etc. are part of the namespace.

Why is this like that? Can't we have a "proper" separation between "pure WebAPI" and MVC application? Is that the correct way of doing thing? If no, what is the correct way of creating a "pure WebAPI"?

Thanks and have a nice day :).