how to add variables such as user to process definition custom error message text

Peoplesoft Version 9.2 HCM & FSM

Hi Peoplesoft Specialists

1 - I am trying to add more information to the delivered PeopleSoft process definition Error Custom Message text section such as display the user who ran the process within the output email received.

Since the Process Instance and Process Name are delivered on the display, I am hoping more process variables are available to display within the email text

2 - what values can be displayed within the delivered System Message: shown in the sample output below

The bottom verbiage is what I currently put into the PeopleSoft Process Definition Error Message, Customized Message text box