Public language
The caller asks for the business outcome, not the internal join strategy.
For order creation with item, delivery, and customer context, the public contract lets the caller request the outcome directly. It does not require the caller to reason through every internal inventory, pricing, tax, or fulfillment record needed to satisfy the system's implementation. That is the server's job.
A cleaner request surface makes the system more capable and less leaky.
Outcome request
The caller states the desired business action in a way that matches the real workflow.
Server orchestration
The implementation can still create whatever hidden records, linkages, or validations it needs behind the curtain.