FPF Reference

A.6.B:5 — Quadrant specifications

Preface node heading:a-6-b-5-quadrant-specifications:7092

Content

This section is the normative “API” of the square: what each quadrant is for, how it is written, and what it must not contain.

A.6.B:5.1 — Quadrant L: Laws & Definitions

Intent. State truth‑conditional content: definitions, invariants, typing/well‑formedness constraints, equational laws.

Adjudication. In‑description: can be checked by inspection, proof, type validation, or model reasoning.

Canonical form. Definition: / Invariant: / predicate‑style constraints using “is / iff / for all”.

Prohibitions.

  • An L-* statement MUST NOT contain RFC deontic keywords (MUST/SHALL/SHOULD/MAY) as operators inside the law/definition itself.
  • An L-* statement MUST NOT encode runtime gate predicates (those are A-*).
  • An L-* statement MUST NOT assert evidence availability or measurement outcomes (those are E-*).

A.7 anchoring. L-* claims are Descriptions: they specify semantics of the signature/mechanism description, not work.

Typical dependence. A-* and E-* claims may reference L-* IDs for vocabulary, metric definitions, and invariants needed for interpretation.

A.6.B:5.2 — Quadrant A: Admissibility & Gates

Intent. Specify when a mechanism application is permitted/admissible: runtime entry predicates, authorization gates, validity gates, applicability checks that require context or execution environment.

Common mistake #0 — Applicability ≠ Admissibility (informative). Signature Applicability scopes intended use/bounded context; it is not a runtime entry gate. Runtime entry checks and permission predicates belong in U.Mechanism.AdmissibilityConditions as A-*. If your prose reads like “clients must satisfy the applicability”, you almost certainly want a D-* duty + an A-* gate (linked by ID) instead.

Adjudication. In‑work: evaluated at mechanism entry (or operationally at the point the mechanism is applied).

Canonical form. Predicate style, e.g.:

  • “A request is admissible iff …”
  • admissible(x) iff P(x) (conceptual form; no particular syntax is required)

Prohibitions.

  • An A-* statement MUST NOT be placed in U.Signature.Laws.
  • An A-* statement MUST NOT use RFC deontic keywords as if it were an agent obligation. (It is a gate predicate, not a duty.)
  • An A-* statement MUST NOT claim that evidence exists (that is E-*) or that someone must enforce the gate (that is D-*).

A.7 anchoring. A-* claims are Descriptions of a mechanism gate. They are not “what a client must do”; they are “what the mechanism admits”.

Required references (explicit). If an A-* predicate relies on defined terms or invariants, it SHOULD reference the relevant L-* IDs (or at minimum the signature that defines them).

A.6.B:5.3 — Quadrant D: Deontics & Commitments

Intent. State governance: obligations, permissions, prohibitions, commitments, publication duties, operational duties, contractual commitments—always with accountable agents/roles.

Adjudication. In‑description (governance is stated in the spec); compliance may be audited via E-*.

Canonical form. A deontic statement MUST have an accountable subject (agent/role), e.g.:

  • “Client implementers MUST satisfy A-….”
  • “Operators SHALL retain carriers …”
  • “Provider SHALL meet E-… under exclusions …”

Canonical payload (recommended; lintable). When a D-* claim is intended to be lintable/reusable, it SHOULD be representable as a U.Commitment record (A.2.8). Default fields to make explicit:

  • id (often the D-* claim ID),
  • subject (accountable role/party; never an episteme),
  • modality (BCP‑14/RFC keyword family normalized),
  • scope + validityWindow,
  • referents (by ID; e.g., SVC-*, L-*, A-*, E-*, MethodDescriptionRef(...)),
  • optional adjudication.evidenceRefs when the commitment is meant to be auditable,
  • optional source when authority/provenance matters.

Prohibitions.

  • A D-* statement MUST NOT use “the system/service/interface/spec” as the grammatical subject unless the accountable role/party is explicitly named (so the statement is representable as a U.Commitment with an explicit subject, A.2.8). (F.18 is a lexical anchor only.)
  • A D-* statement MUST NOT restate L-* or A-* predicates in new words when an ID exists; it SHOULD reference the ID.
  • A D-* statement MUST NOT pretend that commitments are laws. A commitment is an agent relation, not a truth‑conditional invariant.

A.7 anchoring. D-* claims are primarily about Objects (roles/agents and their duties) or about Carriers (retention/exposure duties), but they are still written as Descriptions.

Required references (explicit).

  • If a D-* statement imposes compliance with a gate, it MUST reference the relevant A-* ID(s).
  • If a D-* statement is meant to be auditable, it SHOULD reference the E-* claim(s) that provide evidence and the carrier classes involved.

A.6.B:5.4 — Quadrant E: Work‑Effects & Evidence

Intent. State what happens in work and how it can be evidenced: observed effects, emitted events, traces/logs/metrics, produced reports, measurement outcomes.

Adjudication. In‑work: checked by running/operating and inspecting carriers produced in work.

Canonical form. An E-* statement SHOULD include the minimum fields needed for adjudication:

  1. Observation/measurement conditions (when/where/how observed; workload/window; triggers)
  2. Carrier class/schema reference (A.7 Carrier) that bears the evidence
  3. Viewpoint/consumer (who uses this evidence and why; ties to viewpointRef discipline)

Prohibitions.

  • E-* statements SHOULD NOT use RFC deontic keywords (they are not obligations; they describe adjudicable effects/evidence).
  • An E-* statement MUST NOT hide a gate predicate; gate predicates are A-*.
  • An E-* statement MUST NOT assign agency (“the interface guarantees …”); if enforceability/commitment is intended, express it as D-* referencing the E-*.

A.7 anchoring. E-* claims are primarily Carrier‑anchored: they assert what carriers exist and how they relate to observed work.

Required references (explicit).

  • If the effect/evidence is conditioned on a gate decision, the E-* statement SHOULD reference the relevant A-* ID(s).
  • If the evidence is interpreted using metric definitions or invariants, the E-* statement SHOULD reference relevant L-* ID(s).