-Opens a ticket unless it's allready open, but only unless transaction
-L<RT::Transaction/IsInbound is inbound>.
+This action automatically moves a ticket to an active status.
+
+Status is not changed if there is no active statuses in the lifecycle.
+
+Status is not changed if the current status is first active for ticket's status
+lifecycle. For example if ticket's status is 'processing' and active statuses are
+'processing', 'on hold' and 'waiting' then status is not changed, but for ticket
+with status 'on hold' other rules are checked.
+
+Status is not changed if it's in the list of C<initial> statuses for the
+current scheme and creator of the current transaction
+is one of the ticket's requestors.