BMC remedy incident fields validation rules via rest api

We are using remedy rest api to create and modify incidents.

This works fine. Now, to create or modify incident through UI, we need to make sure correct values for the respected fields are provided.

For example while create an incident the field first name has maxlength 30 chars. This one we found after creating tons of incident and trial and error.

Is there any list of validation rules ? Or is there any specific workflow to get executed for incident fields validation ?