The syntax used in a Record Producer script to access values from Record Producer form fields is producer.
variable_name. A Record Producer is a type of catalog item that allows users to create records on any table from the service catalog. A Record Producer script is a server-side script that runs when a Record Producer is submitted, and can be used to set values or perform actions on the generated record. The producer object is a global object that represents the Record Producer form and its variables. The variable_name is the name of the variable defined in the Record Producer. References: [ServiceNow Docs - Record producers], [ServiceNow Docs - Record producer script]