@longku1 -
As the sdgtw AC Configure Wiki page states for this Advanced Preconfiguration option:
"(Optional - Only in BMC Remedy Service Desk) Update the alarm_message_length key to the required maximum length of each alarm that the probe generates. The probe trims longer messages to the specified length.
Default: 50"
So the incident will be created but sdgtw probe will trim the message to the configured alarm_message_length (100 in your example) before making the request to create the incident in the BMC Remedy Service Desk. As noted earlier, this key only works for integrations with the BMC Remedy Service Desk. If you need this functionality for any of the other supported service desk applications, that would be considered an enhancement request.