i2y

castella-core

i2y2/17/2026

Build desktop, web, or terminal UIs with Castella. Create widgets, components, layouts, manage reactive state, handle events, and use the theme system.

castella-a2ui

i2y1/25/2026

Render A2UI JSON as native Castella widgets. Parse A2UI messages, handle actions, progressive rendering, data binding, and connect to A2UI-enabled agents.

castella-mcp

i2y1/25/2026

Enable AI agents to introspect and control Castella UIs via MCP. Create MCP servers, expose UI resources, handle MCP tools, and use semantic IDs.

castella-a2a

i2y1/25/2026

Connect to A2A protocol agents from Castella. Communicate with agents, display agent cards, send messages, handle responses, and stream results.