agent_kit 0.1.0

Drop-in Flutter widgets for AI agent UIs — tool-call cards, thinking bubbles, citation chips, plan-progress timelines. Backend-agnostic. shadcn-for-agents.

Changelog

0.1.0 — 2026-06-03

First public release. Drop-in widgets for the non-text parts of AI agent UIs.

Added

• Core models
  • ToolCall + ToolCallState (pending / running / success / failed / cancelled) — immutable snapshots advance via copyWith as streams update.
  • ThinkingStep for reasoning prose with an isStreaming flag.
  • Citation for retrieval sources (id, title, url, snippet).
  • PlanStep + PlanStepState (pending / running / done / failed / skipped) with nested sub-step support.
  • AgentEvent Dart 3 sealed union over the above + AgentEventStream typedef.
  • toJson / fromJson on every model. No code-gen.
• Tool widgets
  • ToolCallCard — collapsible card with animated state icon, args pretty-printed as JSON, smart result preview (string / JSON / image URL), error + retry slot, compact / expanded modes.
  • ToolCallFeed — vertical feed keyed by ToolCall.id.
  • ToolRenderer.register(name, builder) extension API for custom per-tool bodies.
• Thinking widgets
  • ThinkingBubble — pulsing dot indicator, animated streaming label, auto-collapses when the step settles.
  • ReasoningTrace — collapsible numbered reasoning log.
• Citation widgets
  • CitationChip — numbered inline badge, url_launcher tap.
  • CitationCard — favicon, host, title, snippet.
  • CitationList — horizontal scrolling source strip.
• Plan / timeline widgets
  • PlanProgress — vertical stepper with state-coloured markers, nested sub-steps, optional Cancel slot.
  • AgentTimeline — chronological mix of every event kind.
• Composition layer
  • AgentView — stream-in, widgets-out, 5-line integration.
  • AgentEventBuilder — low-level builder for custom layouts.
• Theme
  • AgentKitTheme with fromColorScheme, light(), dark() constructors, per-state colours, density presets, and an AgentKitThemeScope InheritedWidget.

Quality

• 55 unit + widget tests passing.
• flutter analyze with strict casts / inference / raw-types: zero issues.
• RepaintBoundary on every card; stable widget keys per event id.
• No AI-provider SDK dependencies.