Authoritative protocol for pre-work review of epics. Six-stage gating chain — roadmap fit, approach elegance, source discussion mapping, sub-structure coherence, prescription layer, avoided-traps completeness — posted as a structured comment on the epic ticket. Per-agent-per-epic one-shot; subsequent sub pickups cite the prior review. Triggers: Use this skill when an agent is about to pick up its first sub from an unreviewed epic (per model-identity OTHER than the epic's author — you never review your own epic). Also use when a user explicitly requests an epic review, or when an epic is freshly filed and a reviewer pre-validates before any sub pickup begins. Participated in the source Discussion? The participant path narrows the chain; it never exempts it.