The Confluence Cloud OpenAPI specification located here appears to be rather incomplete as far as examples where a POST requires a raw content body in JSON.
For example, the create_footer_comment function requires a CreateFooterCommentModel parameter. (See below).
But the example documentation on how to create one of those has empty JSON in it, leaving the programmer to figure it out for themselves via trial and (mostly) error.

Has anyone had any luck figuring this out? I can do the same function in Postman, just not using the OpenAPI client generated from the spec listed above.