design-interrogation
Relentlessly interview the user about a plan, design, or feature spec to surface unresolved decisions, hidden assumptions, and edge cases. Use when the user says "grill me", "stress-test this plan", "poke holes in my design", "what am I missing", or before committing to a plan that feels under-examined. Unlike /specs (which produces artifacts) this skill produces clarity — it's a thinking tool. Also use proactively in the Research phase when a design doc has implicit decisions that need to be made explicit.