05.1 Arguments
When calling an Action you may pass a number of pre-defined arguments to an action as well as any 06. Fields from the Campaign Type the action will be trigger from.
Arguments may be constants, or references to a field.
To reference a field it must be encoded with a $ and a pair of braces {}, for example referencing the lead field 'phone' would look like ${phone}.
See the set of available 06.02. System Fields.