UserName, ClientCode, and AuthenticationID are used to validate the user's account and permissions.PricingCode is provided to define the pricing tier or contract.OriginState, OriginZip, OriginCountry, DestinationState, DestinationZip, and DestinationCountry.Direction indicates the type of shipment (e.g., outbound).ShipmentDate provides the date of the shipment.Items array details each item in the shipment, including its freight class (ItemClass), weight, dimensions (Length, Width, Height), and piece count (Pieces).Accessorials array, such as residential delivery (ServiceCode: "RES").