Designing APIs for real clients

APIs are user interfaces. The users are other developers, frontend components, scripts, integrations, and sometimes future versions of your own application. A good API makes common actions obvious. It returns the data a caller needs, names concepts consistently, and explains failure clearly enough that the client can recover or show a useful message. Designing from the caller perspective helps avoid endpoints that mirror internal implementation details. The shape of the API should support real workflows, not expose every table and service boundary by accident.