Own the business domain
Do not let provider/session identifiers become business truth.
Developer documentation
The participant changes. The journey continues.
A handoff is a governed change in participation inside the same business journey where the underlying business objective has not changed.
Principles
Use controlled Product contracts and technical specifications for implementation detail.
Preserve correlation
Use execution identity for the business journey while keeping other identities distinct.
Keep policy explicit
Tenant, entitlement, acting capacity, consent and step authority are not interchangeable.
Design for failure
Retry, fallback, handoff and recovery should be bounded and observable.
Keep evidence classified
Observed data, calculated metric, inference, recommendation and approved action remain distinct.