A rule consists of information that you want to apply to a shipment. This information is split into categories of fields that correspond to fields on the shipment master table—XMSHDR0—and the shipment item table.

Multiple rules can exist within a rulebook, and you can nest rulebooks. A rulebook contains a collection of rules and rulebooks, along with a number of conditions that specify when a particular rule or rulebook in the top-level rulebook applies to a shipment. These conditions are known as rule determinations in PRECISION. For each shipment that is created in PRECISION, the rule logic runs and compares the characteristics of the shipment with the rule determinations in any rulebooks attached to the shipment. When a rule determination in a rulebook matches a shipment, the rule or rulebook assigned to that rule determination “fires”. When a rule fires, it updates the fields in the shipment based on the information that you specify in the rule fields.