OptionalcontactThe contactProperties field is a map of contact property values. Each contact property value contains a name and value property. Each property will get set on the contact record and will be visible in the template under {{ contact.NAME }}. Use these properties when you want to set a contact property while you’re sending the email. For example, when sending a reciept you may want to set a last_paid_date property, as the sending of the receipt will have information about the last payment.
OptionalcustomThe customProperties field is a map of property values. Each property value contains a name and value property. Each property will be visible in the template under {{ custom.NAME }}. Note: Custom properties do not currently support arrays. To provide a listing in an email, one workaround is to build an HTML list (either with tables or ul) and specify it as a custom property.
The content ID for the transactional email, which can be found in email tool UI.
Static ReadonlyattributeStatic Readonlydiscriminator
A request to send a single transactional email asynchronously.