brainstorm
Brainstorm a feature, architecture change, or refactor and produce a dated design spec. Use this whenever the user says "brainstorm", "let's design X", "how should I build Y", "what's the best approach for Z", "should we use A or B", or is about to start any non-trivial feature, architecture change, or refactor — even if they don't explicitly say "brainstorm". Also use when deciding between two or more design directions. Collaborates via one clarifying question at a time (with a recommended answer), proposes 2-3 approaches with trade-offs, presents the design in sections for incremental approval, and writes a dated spec. Does NOT implement — handoff is to craft:implement in a separate session. Optional browser Visual Companion for UI mockups and visual A/B selection.