Host and UI

Product interaction, composition, and shared presentation contracts.

Load only the contract that owns the changed surface:

Question	Contract
Form factor, chrome placement, or usable canvas geometry	Editor Chrome
Canvas color inspection or structured layer eligibility	Canvas Inspector
Tokens, recipes, primitives, surfaces, or layers	Visual system
Visible product copy or localization	Interface content
Modal composition	Dialog surfaces
Host control geometry, icon, or state	Core Host icon controls

Business rules remain with the owning domain; verification routes are selected by the changed contract in Quality.

Domain Reference

Capability owners, public contracts, and non-obvious boundaries.

Editor Chrome

Editor layout, form factor, viewport, and layer ownership.