Almost all APIs have a way of how problems and errors can be reported, making it easier to understand for the API consumer that something went wrong, and what went wrong. How to do that depends on the API style, API technology, and the specific API design. In all these cases, this part of API design needs to be addressed as part of the overall design work.
For APIs using the Hypertext Transfer Protocol (HTTP), some minimal reporting can be done using HTTP’s status codes. HTTP status codes are interesting because they already provide a certain level of details, with ~60 different codes reporting a variety of conditions which are defined by HTTP itself and a few other specifications.