If you created a new trigger state machine program file, the Trigger State Machine code editor window will be populated with a simple trigger state machine by default (see the following figure).
The simple default trigger state machine program is designed to be valid for any ILA core configuration regardless of debug probe or trigger settings. This means that you can click the Run Trigger for the ILA core without modifying the trigger state machine program.
However, it is likely that you will want to modify the trigger state machine program to implement some advanced trigger condition. The comment block at the top of the simple state machine shown in the previous figure gives some instructions on how to use the built-in language templates in the Vivado IDE to construct a trigger state machine program (see the following figure). A full description of the ILA trigger state machine language, including examples, is found in Trigger State Machine Language Description.