What do people understand when they read “API specification?” I feel most people think it refers to the API description document. Most people simply call the API description the spec. In that case, what do they call the type of specification, e.g., OpenAPI, AsyncAPI? We should call it a format.

Here are the two definitions that matter:

• API specification: a formal, structured document that describes how an API works, what it can do, how to use it, and what developers should expect from it.
• API format: how the API itself is documented or modeled, including its structure, endpoints, data types, and authentication. Popular API formats include OpenAPI, AsyncAPI, GraphQL SDL, and Protocol Buffers.