@ag-ui/proto

@ag-ui/proto

Protocol Buffer encoding/decoding for Agent-User Interaction (AG-UI) Protocol events.

@ag-ui/proto provides high-performance binary serialization of AG-UI events using Protocol Buffers. It includes generated TypeScript definitions and utilities for converting between AG-UI's JSON event format and compact binary representation.

Installation

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

Features

• ⚡ High performance – Binary protobuf encoding for minimal bandwidth usage
• 🔄 Round-trip safety – Compatible conversion between JSON and binary formats
• 📋 Generated types – Auto-generated TypeScript definitions from .proto schemas
• 🔧 Length-prefixed – Standard 4-byte length headers for streaming protocols
• 🖼️ Multimodal snapshots – Supports multimodal user content parts in message snapshots

Quick example

import { encode, decode, AGUI_MEDIA_TYPE } from "@ag-ui/proto";
import { EventType } from "@ag-ui/core";

const event = {
  type: EventType.TEXT_MESSAGE_START,
  messageId: "msg_123",
  role: "assistant",
};

// Encode to binary protobuf format
const encoded = encode(event);

// Decode back to AG-UI event
const decoded = decode(encoded);
console.log(decoded); // Original event object

Documentation

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

Contributing

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

License

MIT © 2025 AG-UI Protocol Contributors