prefix-first-design

# Prefix-First Design A session framework for designing and shipping with AI tools (Cursor, v0, ChatGPT, agents). The brief is the scaffold: protect the stable parts so the dynamic parts can move freely. The scaffold quality determines what gets built on it. Vocabulary: the **brief** is the stable base (the "prefix"). A **locked decision** is one the next phase builds on. The **session close-out** is the decision ledger you carry forward — written for two readers: you (skim) and the next agent (instructions). --- ## Light path vs full path - **Light path** — paste [`SKILL-compact.md`](SKILL-compact.md) as message one. One session, one brief, close-out at the end. Use for exploration days and throwaway prototypes. - **Full path** — this file in the repo, plus a brief / page ledger / decision log that ships with the work, plus monthly still-holds for live products. Use when sessions stack and the product has to stay coherent. Same brief. Same rules. Different weight. --- ## When to use this skill Activate when a user: - Shares a problem frame and asks to prototype or explore design directions - Opens a new design session and needs to establish context - Is mid-session and losing coherence or repeating context - Is handing off work to a developer, stakeholder, agent, or new session - Is working in a repo that contains a brief, page ledger, or decision log Do not activate for one-off questions, quick edits, or tasks with no stated product or user context. --- ##...