Feature Idea: optional restriction for breaks when vehicle is empty.

[Kobe-Kwanten]

Context

Vehicle breaks in cuOpt currently allow defining:

• Break window (when the break may occur)
• Break duration (how long the break lasts)
• Break location(s) (where the break may occur)

Feature Request

We are using cuOpt to solve vehicle routing problems and have a requirement that vehicle breaks may only occur when the vehicle is empty (i.e. its active load/capacity is 0).

From the current documentation, my understanding is that break feasibility is based on the break's time window and optional locations, but not on the vehicle's current load. As a result, the solver may schedule a break while the vehicle is still carrying cargo.

Would you consider adding support for load-based break constraints? For example, an option to require that a break can only be scheduled when one or more capacity dimensions have a load of zero.

If this is already possible with the current API, or if there is a recommended modeling approach to achieve the same behavior, I would greatly appreciate any guidance.

Thank you!