What components are included in the data exchange agreement between the API server and the client application?

The data exchange agreement between the API server and the client application typically includes the following components:

• Data format — for example, JSON or XML, defining the structure of the transmitted information.
• Endpoints (URLs) — addresses of the API where the client sends requests.
• HTTP methods — GET, POST, PUT, DELETE, and others, defining the type of operation.
• Request parameters and body — data sent in the request (e.g., URL parameters or JSON in the body).
• HTTP status codes — to inform the client about success or errors (e.g., 200, 404, 500).
• HTTP headers — metadata of the request and response (e.g., authorization, content type).
• Authentication and authorization mechanisms — tokens, API keys, etc.
• Response structure and schema — description of fields and data types returned by the server.

This agreement ensures consistency and predictability in the interaction between the client and server, facilitating development and testing.