AG-UI Protocol

The AG-UI protocol is a shared set of rules that defines how an AI agent talks to a screen. Think of it like a charging port standard: once the shape of the connector is fixed, any manufacturer's charger will fit. In the same way, once a screen follows this protocol, the same agent can be plugged into a chat window, a dashboard, or a sidebar alike.

No matter how smart an agent's reasoning or search is behind the scenes, it's not much use in practice without a screen where people can watch the results in real time and ask follow-up questions. AG-UI standardizes how a question is entered into an input box, how a conversation continues with follow-up questions, and how answers are displayed on screen — so developers don't have to write connection code from scratch every time they build a new interface for an agent.

The protocol was created and released by a company called CopilotKit, and it isn't tied to any single vendor. When companies that build their own agent products, such as Anthropic, publish guides for supporting this protocol, developers are then free to build all kinds of interfaces around it.

The article explains that "AG-UI is an open protocol created by CopilotKit that standardizes how agents and user interfaces interact." A common misunderstanding here is mistaking AG-UI for a technology built by Anthropic — in reality, Anthropic simply published a guide on connecting its own Claude Managed Agents to this external open standard, while CopilotKit remains the actual creator of the protocol.