Conciseness — when designing an API, you should minimize the set of methods, requests, objects, and resources that will be implemented in the developed API. An unnecessary complication of the API makes it difficult to understand and maintain it further.
Consistency — the object hierarchy and queries should be logically related to each other and intuitive to API users. The names of objects and methods should correspond to their purpose. Names of the same objects and parameters must be identical in all API methods.
Extensibility — API design should always consider the potential need for additional call parameters or object fields. It’s better to extend existing calls than to make new ones, complicating the API.