shape-spec

Use when starting a non-trivial feature, change, or refactor before any plan or code is written. Activate for keywords like "spec", "shape", "what should we build", "requirements", "design this", "we need to", "let's add". Produces a written spec covering goals, non-goals, constraints, acceptance criteria, and open questions. Engineering-flavored — does not chase founder framings like demand reality, wedge focus, or…