Mutt claims to be only a MUA. Meaning that it won't directly talk to remote SMTP servers (for sending mail) or remote POP3 servers (for receiving mail). The authors consider that the job of a Mail Transport Agent. It does have the built-in ability to talk to sendmail (or similar) programs for sending mail or to retrieve mail it has a built-in ability to use IMAP servers or some other local mail format stored by some other program (e.g. fetchmail).
IMAP mailboxes are specified with an URL starting with imap://, usually in a format like:
The prefix imaps:// is used for IMAP over an encrypted SSL connection.
send-hook [!]<pattern> <command>
<command> is executed when sending mail to an address matching <pattern>