What does HTTP 415 mean?
The server does not support the request Content-Type.
Common causes and when you see it
Sending form data to a JSON-only API.
How to fix or handle it
Set Content-Type: application/json when posting JSON.
Test it yourself
Send a request with the online API tester, inspect the response with the HTTP header checker, or host an endpoint that returns 415 with the mock API generator to see how your app reacts.
HTTP 415 questions
The server does not support the request Content-Type.
Sending form data to a JSON-only API.
Set Content-Type: application/json when posting JSON.