US Global Mail API Documentation

Every non-2xx response is an RFC 9457 application/problem+json document whose type links to one of the pages below. Branch on the machine-readable code (not the human-readable title). See Errors for the full body shape and handling patterns.

Status	Type	Title
`400`	`bad_request`	The request was malformed.
`401`	`unauthorized`	Authentication is required or the API key is invalid.
`403`	`forbidden`	You are not permitted to perform this action.
`404`	`not_found`	The requested resource was not found.
`405`	`method_not_allowed`	The HTTP method is not allowed here.
`409`	`conflict`	The request conflicts with the current state of the resource.
`415`	`unsupported_media_type`	The request media type is not supported.
`422`	`validation_error`	Your request parameters did not validate.
`429`	`rate_limited`	Rate limit exceeded.
`500`	`internal_error`	An unexpected error occurred.
`502`	`bad_gateway`	An upstream service returned an invalid response.
`503`	`service_unavailable`	The service is temporarily unavailable.
`504`	`gateway_timeout`	An upstream service timed out.