AG-UI with React

The React binding can observe the private native AG-UI session through the same structural getSnapshot and subscribe contract. The session owns protocol execution; the application selects how its observations become a conversation view.

These APIs are experimental, private source-build packages. The backend createSession used by the fixture is a private composition seam, not a public factory exported by @threadplane/react.

Start with native observations

An AG-UI snapshot contains transcript, state, subagents, and root run evidence. These are native fields. They are not automatically a core AgentSnapshot, and observing them does not make every chat component compatible with that snapshot.

The streaming application projects root text rows for TextTranscript and supplies ChatInput with explicit admission and busy state. useAgent(application) observes the resulting application snapshot.

Explore supported boundaries

Start with Quickstart, then read Architecture.

The dedicated guides demonstrate interrupts, tool observations, client tools, subagents, and JSON Render. Each uses an authored protocol and application policy. A partial tool-argument string does not authorize execution.

Keep provider credentials in the backend. The browser chooses an allowed endpoint and sends user actions; it should not receive model credentials. Local thread identity also does not establish server-side saved-history support.