@ag-ui/core

@ag-ui/core

TypeScript definitions & runtime schemas for the Agent-User Interaction (AG-UI) Protocol.

@ag-ui/core delivers the strongly-typed building blocks that every other AG-UI package is built on: message & state models, run inputs and the full set of streaming event types.

Installation

npm install @ag-ui/core
pnpm add @ag-ui/core
yarn add @ag-ui/core

Features

• 🧩 Typed data models – Message, Tool, Context, RunAgentInput, State …
• 🔄 Streaming events – 16 core event kinds covering assistant messages, tool calls, state updates and run lifecycle.
• ✅ Runtime validation – schemas catch malformed payloads early.
• 🚀 Framework-agnostic – works in Node.js, browsers and any agent framework that can emit JSON.

Quick example

import { EventSchemas, EventType } from "@ag-ui/core";

// Validate an incoming event
EventSchemas.parse({
  type: EventType.TEXT_MESSAGE_CONTENT,
  messageId: "msg_123",
  delta: "Hello, world!",
});

Documentation

• Concepts & architecture: docs/concepts
• Full API reference: docs/sdk/js/core

Contributing

Bug reports and pull requests are welcome! Please read our contributing guide first.

License

MIT © 2025 AG-UI Protocol Contributors