When is it appropriate to use POST instead of GET for retrieval?

POST is advisable to use instead of GET for data retrieval in the following cases:

• When the request contains a large amount of data (for example, complex filters) that is inconvenient or impossible to transmit via URL parameters in GET.
• If you need to hide request parameters from being displayed in the URL (for security or privacy reasons).
• When the request might change the server state (although in this case, it is no longer "retrieval" in the classic sense).
• If the server expects a request body with parameters, which is not supported in GET.

It is important to remember that GET requests should be idempotent and safe, whereas POST is not. Therefore, for pure data retrieval, GET is preferable if possible.

Example: searching with multiple filters passed in JSON in the POST request body to avoid long URLs and browser limitations.