Separate fact time from record time

Intent

I want to keep the date of a fact’s effect separate from the dates of observation and recording.

Correct formFrozen execution sceneBoundary

Wrong form and why it stays silent

Incorrect form

evidence Doc: Record { status verified; observed_at @2026-09-03; }

On an assertion the observed/recorded fields allow Date. On evidence the observed_at/recorded_at fields require Instant: neighbouring carriers have different contracts.

Correct form

Arxo Law

language "law.core" version "0.2";
package recipes.d.r08 version "0.1.0";
namespace "urn:recipe:d-evidence:08";

entity Person;
entity Record;
relation eligible(p: Person);
assert eligible(entity_ref("urn:recipe:d-evidence:08:p")) {
    id "urn:recipe:d-evidence:08#entry"; origin external_snapshot;
    valid [@2026-09-01, @2026-09-10);
    observed @2026-09-03; recorded @2026-09-12;
}

Frozen execution scene

In the table P and Q are different entities of the page, C is a case; full identifiers are pinned in the scenes.

Input on 13.09.2026 (a different date is named in the scene)	Question	Answer
before the start	truth(eligible(P))	NEITHER / COMPUTED
inside the window	truth(eligible(P))	TRUE_ONLY / COMPUTED
excluded right bound	truth(eligible(P))	NEITHER / COMPUTED
knowledge cut before recording	truth(eligible(P))	TRUE_ONLY / COMPUTED

before validity window gives neither

Arxo Law

test "before validity window gives neither" {
    given {
        context {
            legal_time @2026-08-31;
            decision_time @2026-09-13T09:00:00Z;
            knowledge_time @2026-09-13T09:00:00Z;
            timezone "UTC";
        }

    }
    evaluate truth(eligible(entity_ref("urn:recipe:d-evidence:08:p")));
    expect truth_status == NEITHER;
    expect evaluation_status == COMPUTED;
    expect issue(ASSERTION_OUTSIDE_VALID);
}

inside validity window establishes

Arxo Law

test "inside validity window establishes" {
    given {
        context {
            legal_time @2026-09-05;
            decision_time @2026-09-13T09:00:00Z;
            knowledge_time @2026-09-13T09:00:00Z;
            timezone "UTC";
        }

    }
    evaluate truth(eligible(entity_ref("urn:recipe:d-evidence:08:p")));
    expect truth_status == TRUE_ONLY;
    expect evaluation_status == COMPUTED;

}

excluded right bound rejects

Arxo Law

test "excluded right bound rejects" {
    given {
        context {
            legal_time @2026-09-10;
            decision_time @2026-09-13T09:00:00Z;
            knowledge_time @2026-09-13T09:00:00Z;
            timezone "UTC";
        }

    }
    evaluate truth(eligible(entity_ref("urn:recipe:d-evidence:08:p")));
    expect truth_status == NEITHER;
    expect evaluation_status == COMPUTED;
    expect issue(ASSERTION_OUTSIDE_VALID);
}

early knowledge cut keeps established truth

Arxo Law

test "early knowledge cut keeps established truth" {
    given {
        context {
            legal_time @2026-09-05;
            decision_time @2026-09-13T09:00:00Z;
            knowledge_time @2026-09-04T09:00:00Z;
            timezone "UTC";
        }

    }
    evaluate truth(eligible(entity_ref("urn:recipe:d-evidence:08:p")));
    expect truth_status == TRUE_ONLY;
    expect evaluation_status == COMPUTED;

}

Counterfactual

Diagnostic mutation (lower-case) — LDC-E1307.

Original fragment:

Arxo Law

relation eligible(p: Person);

Replacement:

Arxo Law

relation eligible(p: Person);
case Bad { evidence Doc: Record { status verified; observed_at @2026-09-03; } }

The paired scenes above pin the change of outcome.

Boundary

On this path ingest filters valid by legal_time; observed/recorded are kept for audit, but themselves do not cut an assertion by knowledge_time. A historical snapshot is chosen by the supplier; explicit available for documents is shown in Accept admissible evidence. We do not promise an automatic bitemporal filter where there is none.

Date in evidence is checked by lowering the case (lower-case): a single check still does not execute transport. The refusal form in the sidecar places the document in case Bad. An ordinary assertion carries only a weak bound on knowledge time; availability of policy documents has a separate executable slot.

Pitfall

On an assertion the observed/recorded fields allow Date; on evidence the observed_at/recorded_at fields require Instant: neighbouring carriers have different contracts.