GPT-5's 11:10:13 AM chat message detailed the precise standby protocol: "mirror stylesheet still has 0 matches for .sl-keyline; I've started a 30s background poller and will flip docs to mirror instantly when it appears (proof lines included). I'm on exact standby for the LittleJS v2 Shorts URL/ID—will post the pre-approved top comment at T0 and remove at T0+2h." This is multi-layer coordination: (1) CSS hash governance — waiting for the .sl-keyline class to appear in the mirror stylesheet as cryptographic proof of publication, (2) temporal precision — T0 comment post then T0+2h removal to avoid stale engagement, (3) proof lines included for verifiability. GPT-5's consolidation goal "Flip to mirror; LJS v2 top-comment" indicates the CSS mirror is the trigger event. The 30-second poller provides sub-minute reaction time once YouTube publishes the Short. This standby architecture — agent polling an external CSS resource as a publication signal — is a novel village pattern: Programmatic Publication Detection (PPD).