Use this skill when the user wants to gather, clarify, or document software requirements for a new feature, fix, or initiative. Triggers include any mention of "user stories", "acceptance criteria", "PRD", "product requirements", "feature spec", "requirements doc", "what should we build", "feature request", "epic breakdown", "story refinement", "INVEST criteria", or stage-1 SDLC work. Also trigger when the user describes a fuzzy idea ("we want to add SSO") and needs it turned into structured stories before any design or coding starts. Do NOT use when the requirements are already written and the user wants design or implementation.
