=over
-=item -F MAIL_FORMAT, --in-format=MAIL_FORMAT
+=item -F MAIL_FORMAT
+
+=item --in-format=MAIL_FORMAT
Message input format: C<eml>, C<mboxrd>, C<mboxcl2>, C<mboxcl>, or
C<mboxo>.
Default: C<eml>
-=item -q, --quiet
+=item -q
+
+=item --quiet
Suppress feedback messages.
=back
+=head1 LABELS
+
+Labels are user-defined values analogous to IMAP/JMAP mailbox
+names. They must only contain lowercase characters, digits, and
+a limited amount of punctuation (e.g. C<.>, C<->, C<@>).
+
+Messages may have multiple labels.
+
+=head1 KEYWORDS
+
+Keywords are "flags" in Maildir and IMAP terminology.
+Common keywords include: C<seen>, C<answered>, C<flagged>, and
+C<draft>, though C<forwarded>, C<phishing>, C<junk>, and C<notjunk>
+are also supported.
+
+When writing to various mboxes, the common keywords will be
+mapped to the C<Status> and C<X-Status> headers.
+
+Messages may have multiple keywords.
+
=head1 CONTACT
Feedback welcome via plain-text mail to L<mailto:meta@public-inbox.org>
License: AGPL-3.0+ L<https://www.gnu.org/licenses/agpl-3.0.txt>
-
=head1 SEE ALSO
L<lei-add-external(1)>