Vocabulary Temporal Binding - Design Sketch

Unit ID: vocabulary-temporal-binding Status: Closed (2026-09-25). Superseded by the plan, status record, and validation pack; retained for historical context. Follow-on hardening items are tracked separately under temporal-binding-consumer-hardening. Trigger: commit 65ac4a85e11cc1f8616e3e0c24efd59bf4ca410d ([vocabulary] time-bound binding) Source of truth: ontology/vocabulary/README.md and the extracted spec/vocabulary.ttl.

Problem

Vocabulary now supports more than one permanently unscoped scheme per contract. A voc:SchemeBinding reifies the relationship between a voc:SchemeContract and a specific voc:ConceptScheme edition. A binding is temporally scoped through fnd:TemporallyScoped, may apply in one or more opaque voc:BindingScope contexts, and can be recorded on a versioned record with voc:resolvedUnder.

The ontology states the resolution law in prose but the repository does not yet provide the artefacts needed to make that law reviewable or executable. In particular, there are no vocabulary examples, SHACL constraints, resolution fixtures, executable tests, or cross-layer provenance checks.

Invariants to protect

A binding names exactly one contract and one scheme edition.
Multiple voc:bindingScope values are conjunctive. Separate binding nodes express alternatives. No scope means all contexts.
A binding is applicable only when every named scope holds and its temporal scope contains the resolution time.
Among applicable bindings for one contract, a strict superset of scopes wins. Equal-specificity survivors are a conflict and must never be selected silently.
If no scoped or time-applicable binding wins, voc:boundScheme is the unscoped fallback where present.
A scopeless binding and voc:boundScheme for the same contract must name the same scheme.
voc:resolvedUnder preserves the binding that gave historical concept values their meaning. It must not be re-resolved against today’s bindings.
The mechanism remains domain-neutral. Scope membership, fuzzy label resolution, and concept-level version alignment remain outside Vocabulary.

Proposed deliverables

Normative documentation and decision record

Synchronise docs/architecture/ontology-architecture.md with the layer README, including the implementation table, DL encoding, axiom index, worked pattern, and deferred work.
Add proposed ADR-A85 for the binding model, precedence law, conflict policy, fallback rule, and historical provenance boundary.
Keep the root README and runtime architecture documents unchanged unless a concrete vocabulary-specific inconsistency is found.

Examples and fixtures

Add a small, domain-neutral fixture set under ontology/vocabulary/examples/:

one valid unscoped time-bounded binding
one valid two-scope conjunctive binding
one valid pair of alternative regional bindings
one valid temporal edition handover
one valid historical record using voc:resolvedUnder
one invalid binding missing forContract
one invalid binding missing bindsScheme
one invalid temporal scope
one overlapping equal-specificity conflict
one scopeless binding that disagrees with boundScheme
one historical record whose asserted binding is outside its record time

Fixtures should include the minimum Foundation and SKOS terms needed to validate meaning, without inventing a Vocabulary-owned business scheme or scope catalogue.

SHACL validation

Populate ontology/vocabulary/shapes/constraints.ttl with structural and SHACL-SPARQL constraints for cardinality, temporal interval sanity, fallback agreement, equal-specificity conflicts, and historical provenance. Keep the constraints explicit about the input graph and resolution context. A static ontology graph cannot by itself infer an arbitrary runtime context or time, so context/time-dependent checks may use fixture metadata or a documented validation profile rather than pretending to be OWL axioms.

Use structural.ttl for reusable node shapes and rules.ttl only if a rule is needed for validation. Do not add a rule that silently chooses a winning binding.

Executable resolution and tests

Add a small reference resolver in the repository’s established tooling area, with tests covering:

scope conjunction and no-scope fallback
temporal boundary inclusivity and open-ended validity
strict-superset precedence
equal-specificity conflict refusal
fallback only when no applicable binding wins
agreement between a scopeless binding and boundScheme
deterministic results under triple-order permutation
preservation of resolvedUnder without current-state re-resolution

The resolver is a conformance/reference implementation for the law in the layer README. It must not become a domain-specific runtime or a fuzzy concept matcher.

Cross-layer consumer checks

Add fixtures or contract checks showing how a consumer such as Surface or Eligibility resolves a concept-valued property before reading the selected scheme. Check that existing boundScheme behaviour remains valid for unscoped inputs and that a historical resolvedUnder assertion is retained through a versioned record path. Do not change Surface or Eligibility semantics in this unit beyond the smallest adapter or fixture needed to prove the boundary.

Traceability and handoff

Add a slice validation pack under docs/developer/validation/.
Add traceability rows for ADR-A85 and each invariant above.
Update docs/developer/status/vocabulary-temporal-binding.md after every material action.
Update docs/developer/INDEX.md when the plan, fixtures, tests, or validation pack changes state.

Proposed slice boundaries

Slice	Scope	Validation level	Completion gate
1	ADR-A85, architecture sync, fixture vocabulary and traceability skeleton	L0, L2	Human review of semantic parity and ADR
2	Examples and structural/SHACL-SPARQL validation	L1, L3, L4	Positive and negative fixtures produce expected conformance
3	Reference resolver and deterministic test suite	L1, L2	Conflict and precedence mutations fail the tests
4	Consumer and historical provenance integration checks, final docs	L3, L4	Cross-layer contract passes and validation pack is complete

Each slice should stay within one or two implementation modules. If the resolver, SHACL work, or consumer checks exceed that boundary, split the slice before implementation rather than weakening the validation.

Deliberate non-coverage

No fuzzy label or natural-language concept resolution.
No concept-level version alignment or deprecated-concept policy.
No scope-membership algorithm. Vocabulary receives applicable scopes from its caller.
No live store, runtime scheduler, or backend-specific integration.
No silent conflict resolution or OWL encoding of whole-graph precedence.
No advance of the ontology version IRI until the import and release policy is explicitly decided.