Coding agent
A coding-agent streaming session — prose, tool cards, a live todo list, a colored diff, a prompt box.
It is built from core primitives alone — Text, Row, Column, a ListView, and a TextInput over a cell grid — so a rich agent UI comes down to layout and color. The Agent surfaces widgets package pieces like these (transcripts, tool-call cards, diffs) when you would rather not build them. And because it is an ordinary Fleury tree, the same UI is inspectable as a semantic tree — so a test, or another agent, can read it. See Built for agents.
Try it: type a message in the prompt (or just press Enter) and the next turn streams in.