Where can I find info about Eloqua REST API availability and limits by licensing trim/tier

It appears there are REST API availability constraints for the "basic trim" of Eloqua. While searching the documentation, the only information that I could find was a statement that the Bulk API is available for all trims. I can't find any similar statements regarding the Application API.

I was surprised that there is no mention of this in the online REST API resources. I would have expected something in the "Getting Started" section of resources like that to provide guidance, "certain REST resources or verbs are not available in the basic trim,", ideally with a link to a table with the details. But there is nothing in any API documentation that I could find regarding the Eloqua Application API.