Definition

An itinerary is an ordered sequence of destinations, together with the transportation between them.

Each destination in an itinerary includes the following information:

Name

The destination's name.

Description

A short description of the destination.

Cost

The monetary cost at the destination (e.g., admission fees).

Arrival time

The time of arrival at the destination.

Stay duration

How long the group stays at the destination.

Transportation

The transportation mode, cost, and duration from the previous destination (ignored for the first destination).

Constraint validation

This structured representation allows the framework to validate a proposed itinerary against the meeting constraints — the travel date, budget, and time window — and to compare itineraries in terms of objective metrics such as total cost, total time, and the number of destinations. When a proposed itinerary violates a time or cost constraint, the proposing participant is asked to regenerate it through the retry loop. The objective metrics are also used by the contrastive explanation style, which compares a proposed itinerary with the current one.