The tag space has one statement of its own discriminants: the
`operation_kind_tag_vocabulary!` macro. `PAYLOAD_FREE` carries variants
only, so every derived test obtains the pair from that same invocation
and asserts `$disc == $disc`. The kind side is safe for a reason the tag
side lacks — `OperationKind::discriminant()` is a hand-written match, so
two independent statements exist and the golden lock asserts they agree.
Disposition A: a hand-written literal table supplies the second witness.
The signing mutation, executed at 17c1d67: swapping tags 32 and 33 in
both the discriminant literals and the declaration lines leaves
`PAYLOAD_FREE` emitting ascending discriminants, so every derived
artifact stays byte-identical. Two operations exchanged wire
discriminants and the workspace suite returned 1558/0 — unchanged from
baseline. The three probes already on record swapped literals only,
which reorders the corpus and gets caught; they proved a lock exists,
not that one is missing.
Retires one test, not six: the table duplicates the tag→byte subclaim of
the three retained assertions but does not subsume the kind-and-tag
pairings that contain them, nor G3b's local mutation evidence.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01QjsEnYhm1gPpf6ii2iFxFV