Alem Tuzlak 17d98f5386 fix(showcase/harness): drop reasoning-display keyword fallback
The probe sent "show your reasoning step by step" and accepted any
assistant transcript containing "reasoning", "step", or "thinking".
Those tokens are typical assistant acknowledgements of the prompt
itself, so the keyword fallback always matched regardless of
whether the framework actually surfaced REASONING_MESSAGE_* events
to the frontend — making the assertion non-genuine.

Strict-only behavior now: the assertion requires one of the four
stable role/testid markers (reasoning-block / reasoning-content /
reasoning-default / [data-message-role="reasoning"]) to render
within the timeout. Integrations that rely on CopilotKit's default
reasoning slot without a stable testid will fail this probe — by
design.

Replace REASONING_KEYWORDS export with REASONING_SELECTORS, drop
the readAssistantTranscript helper (no longer needed), and update
the test to exercise the testid-presence success path and the
timeout failure path.
2026-05-07 20:54:39 +02:00
2026-04-07 12:29:28 +02:00
2026-05-01 13:16:49 -07:00
2023-06-30 16:46:26 -07:00

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CopilotKit

Build agent-native applications with generative UI, shared state, and human-in-the-loop workflows.

CopilotKit



What is CopilotKit

CopilotKit is a best-in-class SDK for building full-stack agentic applications, Generative UI, and chat applications.

We are the company behind the AG-UI Protocol, adopted by Google, LangChain, AWS, Microsoft, Mastra, PydanticAI, and more!

https://github.com/user-attachments/assets/6f06c63f-9bd1-4762-99ac-24898ee227bc

Add AI to your app in 1 minute

Features:

  • Chat UI – A React-based chat interface that supports message streaming, tool calls, and agent responses.
  • Backend Tool Rendering – Enables agents to call backend tools that return UI components rendered directly in the client.
  • Generative UI – Allows agents to generate and update UI components dynamically at runtime based on user intent and agent state.
  • Shared State – A synchronized state layer that both agents and UI components can read from and write to in real time.
  • Human-in-the-Loop – Lets agents pause execution to request user input, confirmation, or edits before continuing.

https://github.com/user-attachments/assets/55bf6714-62a7-4d5d-9232-07747cc0763b

Quick Start

New projects:

npx copilotkit@latest create -f <framework>

Existing projects:

npx copilotkit@latest init

https://github.com/user-attachments/assets/7372b27b-8def-40fb-a11d-1f6585f556ad

What this gives you:

  • CopilotKit installed – Core packages are fully set up in your app
  • Provider configured – Context, state, and hooks ready to use
  • Agent <> UI connected – Agents can stream actions and render UI immediately
  • Deployment-ready – Your app is ready to deploy

Complete getting started guide →

How it works:

CopilotKit connects your UI, agents, and tools into a single interaction loop.

CopilotKit Diagram — Motion x2 6 sec version

This enables:

  • Agents that ask users for input
  • Tools that render UI
  • Stateful workflows across steps and sessions

⭐️ useAgent Hook

The useAgent hook is a proper superset of useCoAgent and sits directly on AG-UI, giving more control over the agent connection.

// Programmatically access and control your agents
const { agent } = useAgent({ agentId: "my_agent" });

// Render and update your agent's state
return <div>
  <h1>{agent.state.city}</h1>
  <button onClick={() => agent.setState({ city: "NYC" })}>
    Set City
  </button>
</div>

Check out the useAgent docs to learn more.

https://github.com/user-attachments/assets/67928406-8abc-49a1-a851-98018b52174f

Generative UI

Generative UI is a core CopilotKit pattern that allows agents to dynamically render UI as part of their workflow.

https://github.com/user-attachments/assets/3cfacac0-4ffd-457a-96f9-d7951e4ab7b6

Compare the Three Types

image

Explore:

Generative UI educational repo →

🖥️ AG-UI: The Agent–User Interaction Protocol

Connect agent workflow to user-facing apps, with deep partnerships and 1st-party integrations across the agentic stack—including LangGraph, CrewAI, and more.

AG-UI


npx create-ag-ui-app my-agent-app
Learn more in the AG-UI README →

🤝 Community

Have questions or need help?

Join our Discord →
Read the Docs →
Try Copilot Cloud →

Stay up to date with our latest releases!

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🙋🏽‍♂️ Contributing

Thanks for your interest in contributing to CopilotKit! 💜

We value all contributions, whether it's through code, documentation, creating demo apps, or just spreading the word.

Here are a few useful resources to help you get started:

📄 License

This repository's source code is available under the MIT License.

S
Description
copilotkit-debug: Use when diagnosing CopilotKit issues -- runtime connectivity failures, agent not responding, streaming errors, tool execution problems, transcription…; copilotkit-develop: Use when building AI-powered features with CopilotKit v2 -- adding chat interfaces, registering frontend tools, sharing application context with agents,…; copilotkit-agui: Use when building custom agent backends, implementing the AG-UI protocol, debugging streaming issues, or understanding how agents commun…
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