A protocol between an agent and your front end, so the UI can show what it is doing. Built by CopilotKit.
Others in protocols and tools
Agent2Agent
ComposioHundreds of tools, with auth already handled.
FastMCP
Model Context ProtocolThe standard that plugs any agent into any tool.Common questions
Is AG-UI free to use?
AG-UI is open source and free to run yourself. You still pay whichever model provider you point it at, and this tutorial is free with no signup.
Do I need to know Python to use AG-UI?
Basic Python is enough. Functions, dictionaries and imports cover most of what AG-UI asks of you.
When should I not use AG-UI?
When something else in protocols and tools fits the job better. The others in that group are listed below.
Lessons for AG-UI are being written. Meanwhile the APIs for AI tutorial covers the same ground: state, tools, loops, memory and human approval. Most of it carries straight over.
Start the APIs for AI tutorial →