Round-8 review found a tautological assert in this script — it compared a dict
against the comprehension that had just built it, so it could never fire, in the
very script written to fix a provenance-honesty defect. The first repair
(comparing kept[k] to t[k]) was tautological for the same reason; a negative test
confirmed it did not catch a tampered input.
No check inside a transformer can detect a corrupted input, because the
transformer is what defines the output from that input. Both vacuous checks are
removed and the lesson is recorded in the code. The header and the embedded
_provenance now say that fields are carried through BY CONSTRUCTION — a property
a reviewer reads — and name the guarantees that can actually fail: the pinned
upstream SOURCE_SHA256, the requirement that sk be present to be dropped, the
expected group and per-group test counts, and verify mode's byte-comparison of
the committed file. The last two were negative-tested: removing sk aborts with
'has no field sk to drop', deleting a test aborts with 'group 19 has 13 tests'.
The script is also now described as re-runnable EVIDENCE rather than a gate: it
needs network access, so nothing invokes it automatically.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
