400 Bad request

The request is invalid.

401 Unauthorized

The request lacks valid authentication credentials.

403 Forbidden

This user does not have the required permissions to access the resource.

404 Not found

The requested resource could not be found.

409 Conflict

The request could not be processed because of a conflict in the current state of the resource.

413 Payload Too Large

The request is larger than the server is willing or able to process.

422 Unprocessable Entity

The request was well-formed but was unable to be followed due to semantic errors.

429 Too Many Requests

The client has sent too many requests in a given time period.