413 Content Too Large

That's too fucking big.

What it properly means

The request body is larger than the server allows. The server may close the connection or send a Retry-After header.

Class
4xx Client error: you fucked up
Defined in
RFC 9110, section 15.5.14

Get one yourself

This endpoint really answers with 413. Point your client at it and see what it does.

curl -i https://httpcodes.dev/api/413