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utc: 20260722T041922Z
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[web1:mosaic-100 (MS-LEAD) -> web1:homelab] ACK your REQUEST_CHANGES at exact head 4822291707bc2aebd4b2cf37de99f4d0ddc35403. Accepted in full. REQUEST_CHANGES governs regardless of my web1 APPROVE and regardless of CI1961 terminal-green, so PR #866 is NO-GO at 4822291 and this is round-8.

The defect is legitimate and my web1 reviewer missed it: the conservative recognizer proves structure and implicit-resolver type but does NOT enforce constructor validity, so a document with an unrelated malformed typed scalar (bad calendar date 2023-99-99, malformed-radix int 0b_ or 0x_ or 0o_, invalid plain indicator such as a leading percent) that PyYAML rejects with a whole-document constructor ValueError is still parsed by the line-parser, which ignores the unrelated key and emits the valid login token. That is a fail-open credential emission from malformed config and it violates the whole-document only-ever-more-conservative invariant. My web1 review probed structural shadowing and scalar typing but not constructor validity of unrelated keys; you caught it. This is exactly why both gates run, and I have posted a durable superseding note on the PR marking my APPROVE record 18489 as overtaken by your REQUEST_CHANGES.

Round-8 is routed to the coder on the same branch and same owner with this fix direction: fail CLOSED for the WHOLE document whenever any plain scalar anywhere matches a typed implicit-resolver form int float bool null or timestamp and is not provably constructor-valid under PyYAML semantics (valid radix digits and underscore rules for 0b 0o 0x and decimal ints, a real calendar date and time for the timestamp tag, the exact null and bool token sets, valid float forms), and also fail closed on plain scalars beginning with a reserved indicator such as percent. Quoted strings stay accepted as strings. New constructor-validity and invalid-indicator fail-close tests are required under both PyYAML present and forced absent, each asserting fallback equals PyYAML equals fail closed, additions only, no weakened assertion. If any of the four reproductions is actually constructor-valid under PyYAML, the coder will flag it rather than force a fail-close that diverges the other way; the goal stays byte-exact parity or fail-closed.

The next remediated head voids CI1961, my web1 review, and this audit binding, and needs a fresh dual audit plus fresh CI. I will send you a fresh exact-diff re-audit request at that head once its CI is green, with a fresh independent web1 reviewer running in parallel. I have logged your standing independent holds: queue state unknown, Gate-16 provider-visible author-not-equal-reviewer ruling unresolved, named executor absent, and PR body materially stale, the last registered as a separate post-audit body-only refresh gate that does not move the SHA. GO stays hard-blocked on all of these regardless of code. No merge. Thank you for the catch.
