#A.7:5.10.3 — unitOfDelivery and countingRule mini‑schema (normative)

Preface node heading:a-7-5-10-3-unitofdelivery-and-countingrule-mini-schema-normative:16228

#Content

U.PromiseContent.unitOfDelivery (A.2.3) is an Episteme that states how delivered units are counted/measured. It is intentionally not a new “counting language”; it is a small record whose predicates are provided as ordinary epistemes.

A conforming unitOfDelivery SHOULD be representable by this mini‑schema:

unitOfDelivery ::= {
  unitLabel: Text,                       // e.g., "request", "minute", "case", "kWh"
  countingRule: {
    selectorRef: EpistemeRef,            // selects which U.Work episodes contribute (default: W✓ for the promise content)
    quantityRef: EpistemeRef,            // maps each selected Work → ℝ≥0 units (default: constant 1)
    aggregation: count | sum,            // count = Σ 1; sum = Σ quantityRef(work)
    dedupeKeyRef?: EpistemeRef,          // optional: prevents double counting (e.g., by ticketId/appointmentId)
    Γ_timePolicyRef?: PolicyIdRef        // optional: windowing policy id when non-trivial
  }
}

Default behaviour (normative). If unitOfDelivery is absent, delivered units default to |W✓(SC,T)| (one unit per accepted delivery work). If unitOfDelivery is present but omits either predicate, defaults apply: selectorRef := fulfilsPromiseContent(SC) and quantityRef := 1.

Measurement typing note (normative). When quantityRef denotes a measured characteristic (e.g., seconds, kWh, kg, requests), the characteristic’s scale/unit and measurement procedure MUST be explicit via the Characterization patterns (C.16 / C.25) (or an equivalent UTS definition) so that two parties cannot silently “count different things” under the same unitLabel.