layers-intro

This skill is the orientation and entry point for the "Layers of Product Design" framework, meant to be loaded at the start of any design session because every other `/layers-*` skill depends on the context it establishes. It presents design as decision-making: organising work into seven layers across three zones (reality, problem space, and solution space), where lower layers are foundations for upper ones and weak foundations propagate UX debt upward. The seven layers run from observed behaviour and the domain and user needs, up through product strategy, conceptual model, interaction structure, and finally surface.

The skill's substance is a set of operating principles and a usage model. It defines four kinds of design progress — making decisions, uncovering unmade decisions, evaluating existing decisions, and prioritising them — and stresses that uncovering and evaluating are often more valuable than resolving. It instructs the practitioner to treat each layer skill as a technique library rather than a script: find the live decisions, offer a fitting technique, and capture only the residue instead of generating heavy artefacts. Ten cross-session principles reinforce this, including working one layer at a time, checking foundations before building upward, flagging bad decisions rather than only missing ones, and the "push forward, pull back" idea of probing an upper layer to learn what a lower one actually needs. A dedicated section draws attention to frequently overlooked temporal decisions at the conceptual-model and interaction layers.

The target users are product designers, UX practitioners, and teams adopting this framework. It is a conceptual guide and methodology primer with no code, tools, or side effects — useful whenever someone wants a shared vocabulary and disciplined approach for structuring product-design work.