AG-UI standardizes how AI agents connect to front-end applications through an open protocol. Think of it as a universal translator for AI-driven systems- no matter what language an agent speaks: AG-UI ensures fluent communication.

See AG-UI in Action

Check out the AG-UI GitHub repo to explore live examples, usage patterns, and how to bring AG-UI agents into real applications: https://github.com/ag-ui-protocol/ag-ui

Why AG-UI?

AG-UI helps developers build next-generation AI workflows that need real-time interactivity, live state streaming and human-in-the-loop collaboration.

AG-UI provides:

  • A straightforward approach to integrating AI agents with the front-end through frameworks such as CopilotKit 🪁
  • Building blocks for an efficient wire protocol for human⚡️agent communication
  • Best practices for chat, streaming state updates, human-in-the-loop, and shared state

Existing Integrations

AG-UI has been integrated with several popular agent frameworks, making it easy to adopt regardless of your preferred tooling:

  • LangGraph: Build agent-native applications with shared state and human-in-the-loop workflows using LangGraph’s powerful orchestration capabilities.
  • CrewAI Flows: Create sequential multi-agent workflows with well-defined stages and process control.
  • CrewAI Crews: Design collaborative agent teams with specialized roles and inter-agent communication.
  • Mastra: Leverage TypeScript for building strongly-typed agent implementations with enhanced developer experience.
  • AG2: Utilize the open-source AgentOS for scalable, production-ready agent deployments.

These integrations make it straightforward to connect your preferred agent framework with frontend applications through the AG-UI protocol.

Architecture

At its core, AG-UI bridges AI agents and front-end applications using a lightweight, event-driven protocol:

  • Front-end: The application (chat or any AI-enabled app) that communicates over AG-UI
  • AI Agent A: An agent that the front-end can connect to directly without going through the proxy
  • Secure Proxy: An intermediary proxy that securely routes requests from the front-end to multiple AI agents
  • Agents B and C: Agents managed by the proxy service

Technical Overview

AG-UI is designed to be lightweight and minimally opinionated, making it easy to integrate with a wide range of agent implementations. The protocol’s flexibility comes from its simple requirements:

  1. Event-Driven Communication: Agents need to emit any of the 16 standardized event types during execution, creating a stream of updates that clients can process.

  2. Bidirectional Interaction: Agents accept input from users, enabling collaborative workflows where humans and AI work together seamlessly.

The protocol includes a built-in middleware layer that maximizes compatibility in two key ways:

  • Flexible Event Structure: Events don’t need to match AG-UI’s format exactly—they just need to be AG-UI-compatible. This allows existing agent frameworks to adapt their native event formats with minimal effort.

  • Transport Agnostic: AG-UI doesn’t mandate how events are delivered, supporting various transport mechanisms including Server-Sent Events (SSE), webhooks, WebSockets, and more. This flexibility lets developers choose the transport that best fits their architecture.

This pragmatic approach makes AG-UI easy to adopt without requiring major changes to existing agent implementations or frontend applications.

Comparison with other agent protocols

AG-UI focuses explicitly and specifically on the agent-user interactivity layer. It does not compete with protocols such as A2A (Agent-to-Agent protocol) and MCP (Model Context Protocol).

For example, a given AI agent may use MCP to call tools (and get context), A2A to communicate with other agents, and AG-UI to collaborate with a user through a frontend application.

These protocols serve complementary purposes in the agent ecosystem:

  • AG-UI: Deep agent-user collaboration, by bringing agents into frontend applications.
  • MCP: Standardizes tool calls and context handling across different models
  • A2A: Facilitates agent-to-agent communication and collaboration

Quick Start

Choose the path that fits your needs:

Resources

Explore guides, tools, and integrations to help you build, optimize, and extend your AG-UI implementation. These resources cover everything from practical development workflows to debugging techniques.

Explore AG-UI

Dive deeper into AG-UI’s core concepts and capabilities:

Contributing

Want to contribute? Check out our Contributing Guide to learn how you can help improve AG-UI.

Support and Feedback

Here’s how to get help or provide feedback: