The mail send tool can use the email information associated with the job, in addition to email information specified directly in the mail send tool itself.
Specifically:
Use the "Email info" property to explicitly specify email addresses and body text for each and every email being sent by this instance of the mail send tool. You may leave this empty if you only wish to use email info associated with the job (see next bullet item).
Set the "Include attached email info" property to "yes" to also include the email info associated with the job (i.e. the email information that has been accumulated as described in the previous section).
The email addresses specified in the email information are always used in the "To" field of the outgoing email messages. The mail send tool offers a separate "CC addresses" property which allows specifying email addresses to be used in the "CC" field of the outgoing email messages.
It is not possible to associate "CC" addresses with a job (other than in the mail send tool) since email information contains only "To" addresses.