Generative UI

Coverage

The pattern where a language model emits, as structured output constrained by a typed schema, a specification of a UI component or sub-tree that an application then renders for the user. Covers the three load-bearing contracts (component schema, generation constraint, render pipeline), the interaction loop that closes the cycle from user action back into the model's next turn, the trust boundary that makes the rendering safe under adversarial input, the taxonomy by palette openness / generation mechanism / rendering location / interactivity / trust posture, and the distinction from adjacent patterns (chat with markdown, prebuilt-widget routing, RSC streaming as a transport, model-emits-code which is something else).

Philosophy

The conventional model-to-user pipeline is: model emits text; user reads text. Generative UI inverts this: model emits a typed component specification; application renders the specification; user sees a UI surface authored by the application's design system but composed by the model.

This indirection is what makes the pattern simultaneously safe and expressive. Safe, because the application owns the rendering — the model can only ask the application to render components the application has chosen to expose, with data the schema permits. Expressive, because the model can compose components, choose presentations per response, and adapt to the question at hand without the developer pre-building every variant.

The discipline is in the three contracts. The schema must be small enough to be a coherent design vocabulary but expressive enough to cover the assistant's responses. The generation constraint must be reliable enough that the model's emission is always renderable. The render pipeline must enforce schema validation, design-system compliance, and security policies independently of what the model intended. When all three hold, generative UI lets a language model author the choice of what to show without ever touching the rendering surface.

The Three Load-Bearing Contracts