1 files changed, 40 insertions, 0 deletions
diff --git a/lib/Sietima/Role/SubjectTag.pm b/lib/Sietima/Role/SubjectTag.pm
index edaa598..75170d7 100644
--- a/lib/Sietima/Role/SubjectTag.pm
+++ b/lib/Sietima/Role/SubjectTag.pm
@@ -4,12 +4,52 @@ use Sietima::Policy;
 use Types::Standard qw(Str);
 use namespace::clean;
 
+=head1 NAME
+
+Sietima::Role::SubjectTag - add a tag to messages' subjects
+
+=head1 SYNOPSIS
+
+  my $sietima = Sietima->with_traits('SubjectTag')->new({
+    %args,
+    subject_tag => 'foo',
+  });
+
+=head1 DESCRIPTION
+
+A L<< C<Sietima> >> list with this role applied will prepend the given
+tag to every outgoing message's C<Subject:> header.
+
+=head1 ATTRIBUTES
+
+=head2 C<subject_tag>
+
+Required string. This string, enclosed by square brackets, will be
+prepended to the C<Subject:> header of outgoing messages. For example,
+the code in the L</synopsis> would cause an incoming message with
+subject "new stuff" to be sent out with subject "[foo] new stuff".
+
+If the incoming message's C<Subject:> header already contains the tag,
+the header will not be modified. This prevents getting subjects like
+"[foo] Re: [foo] Re: [foo] new stuff".
+
+=cut
+
 has subject_tag => (
     is => 'ro',
     isa => Str,
     required => 1,
 );
 
+=head1 MODIFIED METHODS
+
+=head2 C<munge_mail>
+
+The subject of the incoming email is modified to add the tag (unless
+it's already there). The email is then processed normally.
+
+=cut
+
 around munge_mail => sub ($orig,$self,$mail) {
     my $tag = '['.$self->subject_tag.']';
     my $subject = $mail->header_str('Subject');