By default, we do nothing special with these messages. Many games like to use a distinctive notation for parser messages, to make it clear that the messages are "meta" text that's not part of the story but rather specific to the game mechanics; one common convention is to put parser messages in [square brackets].

If the game defines a special appearance for parser messages, for consistency it might want to use the same appearance for notification messages displayed with the <.notification> tag (see notificationStyleTag).

parserStyleTag :   StyleTag