KFD-4 Implementation Notes
Authoritative decision · Formal reference · Documentation map
KFD-4 defines the perspective rule: views must remain bound to declared
perspectives, and perspective transformations must remain inspectable when they
are used to reveal different objects or guide action. The authoritative text is
decisions/KFD-4.md.
Package Surface
The KFD package implements two connected machine-checkable KFD-4 profiles:
decisions/KFD-4.md: the authoritative principle.schemas/kfd-4/observer-perspective.schema.json: the profile for observer-relative timeline views.schemas/kfd-4/perspective-replay.schema.json: the profile for perspective-preserving and contrastive replay.standards.json#/standards/kfd-4: schema identity, interface contract, and concept names.scripts/check.mjs: package wiring and contract verification.
These profiles implement the first engineering path:
perspective-bound timeline
-> perspective-preserving replay
-> contrastive replay
-> visible cross-perspective object mismatch
They are not a universal model for perspective. Other domains may define their own KFD-4 profiles while preserving the decision’s observer, fact, transformation, causal, degradation, and responsibility boundaries.
When To Use The Gate
Use KFD-4 when observer position can materially change interpretation, ordering, relevance, visible object boundaries, or action. Declare the current perspective and, when a transformation is claimed, what changed and what became newly visible.
For mixed-source timelines, expose view subject, observer, accepted facts, projection policy, causal constraints, degraded evidence, and verification. Schema validity proves that this declaration exists. It does not prove that an adapter captured every fact or that a runtime timeline is complete.
For replay, expose the source views, replay observer, shared context,
reconstruction policy, preserved elements, declared loss, degraded state, and
verification. Contrastive mode requires at least two source views and an
explicit mismatch record. A primitiveSignal: candidate is an input to KFD-5,
not certification.
Choosing The First Genesis Probe
When the KFD-1 through KFD-3 foundation is already installed, use perspective transformation as the default first probe when:
- relevant causal facts are already preserved;
- two or more materially different roles, participants, or consequence positions are available;
- replay loss and degraded evidence can be declared; and
- the suspected gap concerns a hidden object, burden, boundary, or action surface.
In that setting, the marginal operation is to change the declared position, replay existing evidence, and compare what becomes natural. Do not force this profile when source perspectives are unavailable, capture or privacy cost dominates, the target is an in-view statistical anomaly, causal intervention is required, or corpus compression is the cheaper search. Those methods still declare the perspective from which their evidence was selected and hand any candidate to KFD-5 for qualification.
Perspective Transformation Record
A domain-specific record should preserve at least:
- the origin perspective and its natural objects;
- the transformed perspective and consequence-bearing participant;
- the transformation performed;
- the accepted facts and known gaps;
- the burden, boundary, or object that became visible;
- the boundary between local epistemic priority and wider claims.
KFD-5 turns that last output into a primitive candidate and qualifies it.
Foundation Closure And Trust Relation
The two KFD-4 profiles depend on the complete foundation triad. KFD-1 keeps the facts beneath a timeline from drifting. KFD-2 makes replay fidelity, degradation, and responsibility assessable. KFD-3 lets participants expose and compare preserved views through trusted value rather than coercion. Schema validity without those dependencies does not establish a trustworthy perspective transformation.
KFD-4 claims can be assessed by KFD-2. The KFD package’s assessment proves the decision text, timeline and replay profile schemas, standards metadata, and self-check wiring. Adopters own evidence for their runtime view, replay fidelity, or perspective transformation.