# Cloudflare Agents SDK [[Cloudflare]] Agents SDK is a TypeScript framework for building stateful AI agents on [[Cloudflare Workers]] and [[Cloudflare Durable Objects]]. Each agent instance maps to a single Durable Object — giving it strong consistency, persistent SQLite-backed state, WebSocket support, and the ability to schedule its own future work via alarms. The SDK is Cloudflare-specific by design: it leans on Durable Objects' per-instance addressability, Workers' V8 isolate model, and the platform's WebSocket hibernation. It is not a generic agent framework like LangChain — it is "how to write durable agents that live forever on Cloudflare's edge." ## Why It Matters Most agent frameworks treat state as an afterthought — assume external Redis, external DB, external queue. The Agents SDK inverts this: every agent has its own SQLite database inside its Durable Object, can wake up on a schedule, and resumes exactly where it left off after restarts. For long-running agents (research, monitoring, orchestration), this changes the operational model. Pairs naturally with [[Cloudflare Workers AI]] for inference, [[Cloudflare Sandbox SDK]] for code execution, and [[Cloudflare Vectorize]] for memory/RAG. ## Core Primitives - **Agent class**: extends Durable Object, exposes RPC methods, manages state - **State management**: typed via TypeScript generics, persisted automatically - **Scheduled tasks**: agents can call `this.schedule(when, method)` to invoke themselves later - **Real-time**: WebSocket support for streaming responses to clients - **Workflows**: durable, restartable multi-step processes - **MCP servers**: ship agents as Model Context Protocol servers ## Common Use Cases - **Chat agents** with persistent memory across sessions - **Voice agents** with hibernating WebSocket connections - **Browser-automation agents** orchestrating multi-step workflows - **Background workers** that wake up, do work, sleep — for hours, days, weeks - **MCP servers** exposing tools to Claude and other LLM clients ## References - Agents SDK home: https://developers.cloudflare.com/agents/ - GitHub: https://github.com/cloudflare/agents ## Related - [[Cloudflare]] - [[Cloudflare Workers]] - [[Cloudflare Durable Objects]] - [[Cloudflare Workers AI]] - [[Cloudflare Sandbox SDK]] - [[Cloudflare Vectorize]] - [[TypeScript]] - [[Wrangler]]