Introduction

Melony is a fast, unopinionated, minimalist event-based framework for building AI agents.

Melony is designed to be the "Express.js" of the agent world. It doesn't force a specific LLM, orchestration pattern, or UI library on you. Instead, it provides a tiny, high-performance core for routing and handling events.

Why Melony?

Fast & Lightweight: Zero dependencies at its core. A tiny footprint for any JS environment.
Unopinionated: No rigid orchestration loops. You define how events flow through handlers.
Event-Driven: Everything in Melony is an event. Text, tool results, and custom data all flow through a unified stream.
Highly Extensible: Modularize your logic with the Plugin System, or use event handlers to intercept runs, manage state, or implement HITL workflows.
Platform Agnostic: Run your Melony agents anywhere—Edge functions, Node.js, or directly in the browser.
UI-Ready: While unopinionated about UI, Melony's event stream is perfect for building Server-Driven UI (SDUI) experiences.

Core Philosophy

Melony treats the interaction between a user and an agent as a continuous, reactive stream of events.

Instead of a rigid Request/Response model or a fixed "Plan -> Execute -> Observe" loop, Melony provides a fluent builder to wire up event handlers. Your logic can yield events that trigger other handlers, creating complex behaviors from simple, decoupled pieces.

Packages

melony: The core runtime, fluent builder, and lightweight client.
@melony/react: React hooks and providers to render Melony streams and SDUI nodes effortlessly.

Ready to build? Head over to the Getting Started guide.