For AI agents: the complete documentation index is available at https://a3s-lab.github.io/UI/v0.4.1/en/llms.txt, the full documentation bundle is available at https://a3s-lab.github.io/UI/v0.4.1/en/llms-full.txt, and this page is available as Markdown at https://a3s-lab.github.io/UI/v0.4.1/en/components/index.md.

Component overview

A3S UI provides 116 public component contracts. Search by display name, localized name, route slug, or interface responsibility; results preserve the current language and documentation version.

Find components by interface job

Start with the interface job, or search directly when you know the name.

116 components
9 task groups across 116 searchable components

Actions and input

12 components

Create, edit, and submit with actions, fields, and text entry.

Selection and filtering

12 components

Choose and narrow values while preserving native state wherever possible.

Navigation and wayfinding

8 components

Move through pages, hierarchy, and scroll position without losing context.

Application structure

14 components

Structure shells, toolbars, panes, durable regions, and appearance controls.

Overlays and menus

10 components

Handle menus and layered, positioned, or focus-protected interaction.

Feedback and status

9 components

Explain loading, status, outcomes, exceptions, and recovery.

Content and media

13 components

Present prose, media, code, and reusable content surfaces.

Data display

8 components

Organize collections, properties, progressions, and quantitative data.

Harness

30 components

Cover task input, conversation, files, execution approval, review evidence, and development preview.

Choosing a component

  • Prefer native elements for actions, input, and selection so the browser owns focus, form state, and accessibility.
  • Add a component runtime only when the platform does not provide the complete behavior, such as composite selection, resizable panes, or device previews.
  • Page shells, toolbars, and resource layouts provide workspace structure. They do not replace smaller input or feedback components.
  • Task, execution, review, and developer-tool components live in Harness; each one keeps its stable /components/* page URL.

Structured forms

The Form system brings the deterministic Form Core, visual Designer, controlled Renderer, 23 built-in fields, complex collection fields, and durable interaction contracts into the same component information architecture. React Hook Form bindings and Vue composables use the same schema, validation, and submitted-value semantics, with interactive examples embedded directly in the component guides.

API model

API surfacePurposeExample
Root classSelects the componentclass="resource-card"
Native attributesBehavior and accessibilitydisabled, checked, aria-current="page"
data-* attributesFinite visual or behavioral variantsdata-size="sm", data-orientation="vertical"
CSS custom propertiesContinuous layout values and theme decisions--split-position: 40%
JavaScriptBehavior the browser does not provideSplit-pane resizing, device preview, and composite keyboard interaction

Native elements remain the source of truth. A disabled button uses disabled; it does not require a second library-owned state value.

Framework integration

HTML is the public contract for every component. The React and Vue adapters reuse the same semantic root without adding wrappers. A component gets a dedicated hook or composable only when it exposes events or methods. Each component page lists the interfaces that actually exist instead of placeholder APIs.

CapabilityGeneral componentsApplication structureHarness
Semantic HTMLRequiredRequiredRequired
React and VueSemantic-root adapterSemantic-root adapterSemantic-root adapter
Hook or composableWhen behavior APIs existWhen behavior APIs existWhen behavior APIs exist
Light and dark themesSupportedSupportedSupported
RTL logical layoutSupportedSupportedSupported
Responsive layoutComponent-specificBuilt inWorkflow-specific
Nunjucks and JinjaExisting templatesHTML compositionHTML composition

Choose the A3S style pack for new products. Vega, Nova, Maia, Lyra, Mira, Luma, Sera, and Rhea are reserved for applications that must preserve an established appearance.