The message text and subject for any given event reminder can be modified by selecting the Control Panel icon under MyActions, choosing My Management, and then selecting Configure Preferences.



Scroll down until the Reminder Options section is visible.
Here, you will see two boxes, the Message Text box and the Message Subject box. In the Message Text box, you will see the default options $stTime$ - $endTime$: (start time and end time) and $caption$ (the event caption).
If you wish, you may type $description$ in order to receive the event description in the text message reminder.