A.2.3:4.1.2 - Unit-of-delivery counting

Use unitOfDelivery only when a receiving use counts accepted delivery. It is a specification-use episteme carried in the promise content.

An ordinary rule may say: Count one accepted delivery per appointment; rework under the same appointment does not add another unit. When replay or measurement needs a structured representation, use only the fields that rule requires:

UnitOfDeliverySpec : U.Episteme ::= {
  unitDesignator: U.NameToken,
  countingRule: {
    selectorRef: U.EpistemeRef,                   // selects only delivery Work for which fulfilment obtains
    quantityRuleRef: U.EpistemeRef,               // maps selected facts to the count or measured quantity
    aggregationRef?: U.EpistemeRef,
    dedupeKeyRef?: U.EpistemeRef,
    countingPolicyRef?: U.EpistemeRef,
    measurementMethodRef?: U.MethodRef,
    measurementMethodDescriptionRef?: U.EpistemeRef,
    evidenceAdmissibilityRef?: U.EpistemeRef
  }
}

The selector admits only Work occurrences for which the promise’s delivery and acceptance predicates are satisfied. For a cross-promise aggregate using one Work occurrence, or when rework must not add another delivery unit, dedupeKeyRef or the cited counting policy states the intended boundary. Separate per-promise counts may use the default below. A measurement Method, its description, evidence-admissibility rule, evidence epistemes, and evidence-use relations appear only when the count depends on a measurement reading or relied-on evidence. Pure counting needs none of that apparatus.

If unitOfDelivery is absent, the local default is one unit per obtaining PromiseContentFulfilmentRelation occurrence. A separately governed charging relation may consume the resulting quantity but does not define this counting rule.