Contact properties provide the ability to append custom details to your contacts. For example, you can sync values from your other operational systems with iService so agents can use variables to insert account numbers of other frequently used values into responses. You can create an unlimited number of contact properties in your tenant. Since property names are referenced in iService variables, they must be unique across all of your iService segments.
Contact properties are managed in the Segment Settings page of iService and are available for inclusion in agent responses and custom forms using the $value command. Select your segment from the settings menu (1) and then select the Contact properties tab (2).