/message/sendSingle

Sends a prepared message as a single message to a specific user.

This method automatically adds the user who receives the email to the group of the prepared message.
Attachments can be encoded using base64encode.org.
Request body example:

{
"parameters":
    [{"name" : "Parameter Name 1","value" : "Parameter Value 1"},
     {"name" : "Parameter Name 2","value": "Parameter Value 2"}],
     "attachments":
    [{"name" : "image.png",
    "contentType" : "application.png",
    "content" : "BASE64ENCODING"}]
}