Spec Document Reviewer

Purpose: Catch spec gaps BEFORE they survive into exploration, design, and implementation.

When to Dispatch

After Phase 1 (brainstorm) writes .planning/SPEC.md and before Phase 2 (explore) begins.

Phase 1: Brainstorm → SPEC.md written
  → [THIS SKILL] Dispatch spec reviewer subagent
  → Issues found? Fix SPEC.md → re-dispatch reviewer
  → Approved? → Phase 2: Explore

NO EXPLORATION WITHOUT REVIEWED SPEC. This is not negotiable.