411 Length Required
The server requires a Content-Length header.
What it means
The request had a body without a declared length.
What your client should do
Send Content-Length, or let your HTTP library set it.
Should you retry?
Only after you change the request.
Try it
The free practice API returns this status on demand, with the headers a well-behaved API would send. Call GET /api/play/status/411 from Endpoint Client and open the Explain tab.
Defined in RFC 9110. All status codes and headers