Turns a one-line feature idea into a decision tree, interrogates it in batched rounds scaled to how many real sub-decisions it has (not a fixed count), then produces a 2-3 paragraph ready-to-use prompt plus a detailed branch-organized spec file. Use for a short idea that implies a whole feature domain with independent sub-decisions — role-based access, multi-tenancy, notifications, payments, search, a workflow engine. NOT for a single narrow ambiguity (use `interview-me`) or light product ideation (use `idea-refine`).
