If you are wanting to have the 'Whisper Message' (in Settings > Phone Numbers) tell you additional information before you take the call, you can include custom values in the messaging (see first image below):
Tool: Use the 'Templates' editor to create your messaging, then copy and paste into the 'Whisper Message' field.
Examples:
Here are two options you can use. Simply paste the code into the Whisper Message field (don't inlclude the text in BOLD):
Contacts Name with Full Address:
{{contact.name}} is calling about {{contact.full_address}}
Contacts First Name with Address Only:
{{contact.first_name}} is calling about {{contact.address1}}