Email Delivery generated unique Envelope ID of the email submission. If you need to contact Email Delivery about a particular request, please provide the Envelope ID.
The unique ID for the email's Message-ID header used for service log correlation. The submission will return an error if the syntax is not a valid RFC 5322 Message-ID. This will be generated if not provided. Example: sdiofu234qwermls24fd@mail.example.com
Return list of suppressed email addresses.
Response object that is returned to sender upon successfully submitting the email request.