What does HTTP status 200 (Ok) mean?

HTTP_STATUS_OK

For GET, a 200 response normally carries a representation of the requested resource. For POST, it commonly represents the result of the submitted action; for HEAD, headers describe the response without a message body.

A 200 response is cacheable by default unless cache controls or the request method say otherwise. When a newly created resource should be identified explicitly, a server generally uses 201 instead.

Interpret 200 with the request method

For GET, the payload normally represents the selected resource; for HEAD, the same success has no response body; for other methods, the representation can describe the action result. Client code should therefore interpret 200 together with the request method and media type rather than assuming that every 200 body has the same meaning.

RFC 9110: HTTP Semantics