Two prior arcs closed on "the binding constraint is ratified curriculum volume,
not machinery." Verified against code 2026-07-25: the machinery half is wrong in
a load-bearing way, and the correction is the reason this arc exists.
evals/curriculum_serve/practice/ does not exist. seal_ledger exists only for
deduction (evals/deduction_serve/practice/runner.py:96), yet
chat/curriculum_serve_license.py's own docstring names
evals.curriculum_serve.practice.runner.seal_ledger as "the only writer" of the
artifact it reads -- that writer was never built, and
chat/data/curriculum_serve_ledger.json does not exist. And the ceremony stops
short: RatificationReceipt.pending_stages = (arena_queue_entry, ledger_reseal).
So the pipeline is author -> ratify -> ??? -> ??? -> license -> serve. Authoring
curriculum today cannot earn a license at ANY volume. Content is necessary and
currently insufficient. The build is still modest, because oracle.py is already
an independent decision procedure usable as the gold tether and ADR-0263 already
extracted the sealers for exactly a third instance.
Two measured facts shape the content work. `refuted` has NEVER been produced --
the physics lane gold is entailed 14 / unknown 12 / declined 6, and no corpus row
can express it. And bands key on (domain, operator_family), so negative content
must live INSIDE operator_family "modal" with a row-level polarity marker; a
separate modal_negative family would create a new band at n=0 instead of adding
refuted volume to the target band -- the easiest available way to waste the whole
authoring effort.
DIVISION-OF-WORK.md records the tiering criterion and why it is not difficulty.
The evidence does not support a prestige split: in the same 48h window Sonnet 5
found the DEFAULT_SINK bug that wrote outside the repository and did the
six-worktree public_demo archaeology, while Opus 5 mis-diagnosed the CGA hot path
by multiplying a microbenchmark by a call count. Model tier was not the variable;
verification discipline was.
The split is therefore: would an error here be caught by a gate, or is it silent?
Two units are silent-failure BECAUSE THEY ARE THE GATE -- the negative-curriculum
epistemology (wrong => corpus encodes falsehoods and wrong=0 still passes, since
lane gold and the oracle both read the same rows) and the volume-honesty invariant
(wrong => conservative_floor cannot tell 657 independent facts from 16 asked 41
times, so the ledger clears theta=0.99 having earned nothing). Those get Opus.
Everything loud goes to the cheapest competent tier.
Also records the ordering correction: the epistemology ADR must precede the
generator, or the generator gets built twice.
[Verification]: docs-only; no code paths touched. Every referenced path confirmed
to exist and all five line citations confirmed accurate at HEAD (gold.py:1163,
curriculum_serve/runner.py:71, discovery_yield.py:67-70, entail.py:125,
curriculum_surface.py:184). Pre-push gate runs on push.
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