Excursion Descriptive Info message is used to get full excursion offer description. That request returns complete information about the excursion that starts on the date specified in ExcursionRate/ExcursionDate element in Excursion Availability Response.
Diagram 3.1. Excursion Descriptive Info in GP Travel HUB Workflow
WARNINGS AND ERRORS
All Warnings and Errors that could appear during Excursion Descriptive Info Request and Response you can see in ERROR HANDLING section.