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Connect your UI to a Harnest agent through POST /agui. Harnest adapts the AG-UI protocol to its shared runtime, so the same integration works with Google ADK and LangGraph. You can use CopilotKit or another client that supports Harnest’s AG-UI contract. Your agent stays in Harnest. Your frontend owns the conversation UI, browser tool handlers, and approval controls. Authentication, session ownership, request limits, concurrency, timeouts, and cancellation follow the same runtime policy as the neutral API.

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What Harnest supports

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Choose your next step

Connect a client

Start a thread, send a turn, handle failures, and cancel a run.

Share state and context

Pass application data to your agent and keep your UI in sync.

Handle interactions

Resume human approvals, browser tools, and external waits.

Try CopilotKit

Run the local React demo and test both agent frameworks.

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Current boundaries

The AG-UI endpoint accepts text input. For typed or media input, use the neutral API and multimodal contracts. Pending approvals and client-tool exchanges belong to the serving process holding the suspended invocation. Resume them on that process; they are not portable across restarts or replicas. Client context and advertised tools do not grant authority or register executable capabilities.