Order 20260907T074541Z-939882634-from-.claude asked for smoothed-IDF rarity
weighting so no_lexical_match gates on informative tokens, with both
known-negative controls (sveising/titan/vakuum; pingviner/Bouvetoeya) required
to reach delivered == 0 on the real K2 bundle (629 concepts, 39 documents).
Swept the threshold across the full observed IDF range (1.5-7.9) before
building anything, per Verifiseringsloven face 3: verify an input premise
against ground truth before acting on it. The frontier is empty. neg2 first
reaches 0 at T=4.6, and gold-hit reachability has ALREADY fallen to 0 of 6 at
that same T. neg1 does not reach 0 until T=6.4, by which point every positive
question has been unreachable for eighteen threshold steps. The two rarest
tokens in the entire gold set (titan idf 6.059, vakuum idf 6.347) belong to
the sveising question, so rarity weighting scores them as maximally
informative rather than as noise.
Two structural causes, not just a bad threshold pick: (1) df is measured over
the same four-character prefix matcher that collapses brannalarm/branntrapp/
branncelle/brannkonsept into one bucket, so a real topic word reads as the
LEAST rare term in its own question; (2) MIN_TOKEN_LENGTH=3 admits tokens
MIN_SHARED_PREFIX=4 can never match (hva/for/den are structurally df=0),
leaving some positive questions resting on a single surviving token.
No production code changed — the mechanism the order named is falsified
before implementation, so there is no red test to write against it. Returning
the order with this measurement as the reason.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>