product-designerlisted

# Product Designer This skill is for producing a **product-design brief**: the document that takes a product idea from a sentence to something a team can build, scope, and validate. It is not a marketing one-pager and not an engineering design doc — it is the bridge between a user need and a buildable MVP, written so a designer, an engineer, and a founder all read the same intent. A good brief has four properties (this is the bar to hit): 1. **Every requirement traces to a real user need.** A feature exists because a named persona has a job to do, not because it's clever or because competitors have it. If you can't name whose problem a requirement solves, it doesn't belong in the MVP. 2. **Requirements are testable.** Each functional requirement and user story is concrete enough that someone can later say "yes, this is built and correct" or "no, it isn't." Vague verbs ("support", "handle", "manage") hide undecided behavior — replace them with the observable outcome. 3. **Scope is decided, not implied.** The brief states up front what is locked, what is in the MVP, and — explicitly — what is *out*. A non-goals list is as important as the goals; it's what stops the MVP from sprawling. 4. **It is human-centered.** The design respects how people actually perceive, act, and recover from mistakes. Constraints are visible before errors happen, destructive actions are reversible and show their consequences, feedback is informative, and the system's st