agents

Cloudflare Agents

Agents are persistent, stateful execution environments for agentic workloads, powered by Cloudflare Durable Objects. Each agent has its own state, storage, and lifecycle — with built-in support for real-time communication, scheduling, AI model calls, MCP, workflows, and more.

Agents hibernate when idle and wake on demand. You can run millions of them — one per user, per session, per game room — each costs nothing when inactive.

npm create cloudflare@latest -- --template cloudflare/agents-starter

Or add to an existing project:

npm install agents

Read the docs — getting started, API reference, guides, and more.

Quick Example

A counter agent with persistent state, callable methods, and real-time sync to a React frontend:

…

// client.tsx
import { useAgent } from "agents/react";
import { useState } from "react";
import type { CounterAgent, CounterState } from "./server";

function Counter() {
  const [count, setCount] = useState(0);

  const agent = useAgent<CounterAgent, CounterState>({
    agent: "CounterAgent",
    onStateUpdate: (state) => setCount(state.count)
  });

  return (
    

  );
}

State changes sync to all connected clients automatically. Call methods like they're local functions.

The agent is a Durable Object, so it needs a binding and a SQLite migration in wrangler.jsonc:

{
  "name": "counter",
  "main": "server.ts",
  "compatibility_date": "2026-06-11",
  "compatibility_flags": ["nodejs_compat"],
  "durable_objects": {
    "bindings": [{ "name": "CounterAgent", "class_name": "CounterAgent" }]
  },
  "migrations": [{ "tag": "v1", "new_sqlite_classes": ["CounterAgent"] }]
}

Features

Feature Description Persistent State Syncs to all connected clients, survives restarts Callable Methods Type-safe RPC via the @callable() decorator Sub-agents Parent/child DO composition via facets, nested routing, and typed parent lookup Agent Tools Run chat-capable sub-agents as tools with streaming child timelines Scheduling One-time, recurring, and cron-based tasks WebSockets Real-time bidirectional communication with lifecycle hooks AI Chat Message persistence, resumable streaming, server/client tool execution MCP Act as MCP servers or connect as MCP clients (HTTP, SSE, RPC, elicitation) WebMCP Expose page-local tools or bridge remote MCP tools to browser agents Workflows Durable multi-step tasks with human-in-the-loop approval Email Send, receive, and reply via Cloudflare Email Service Voice Continuous STT, streaming TTS, VAD, interruption, SFU utilities Browser Agents Run agents in the browser tab with agents/browser Code Mode LLMs generate executable TypeScript instead of individual tool calls Sandboxed Execution Run generated code inside an isolated Worker with a virtual filesystem x402 Payments Pay-per-call APIs and tools via the x402 protocol Observability Built-in tracing, metrics, and structured logs SQL Direct SQLite queries via Durable Objects React Hooks useAgent, useAgentChat, useVoiceAgent for frontend integration Vanilla JS Client AgentClient and VoiceClient for non-React environments

Packages

Package Description agents Core SDK — Agents, routing, Voice, Channels, scheduling, MCP, workflows, x402, browser agents @cloudflare/ai-chat Higher-level AI chat — persistent messages, resumable streaming, tool execution @cloudflare/think Opinionated chat agent base — agentic loop, stream resumption, client tools, workspace tools @cloudflare/codemode LLMs write executable code that calls your tools, instead of one tool call at a time @cloudflare/shell Sandboxed JS execution + virtual filesystem (Workspace) for agents @cloudflare/voice Deprecated compatibility wrapper for the agents/voice exports @cloudflare/worker-bundler Build and bundle Workers at runtime, for use with the Worker Loader binding hono-agents Hono middleware for adding agents to Hono apps

AI-chat modules used to live in agents/ai-chat-agent, agents/chat, agents/ai-react, and agents/ai-types. Those entry points still re-export, but they're deprecated — import from @cloudflare/ai-chat directly. New chat-from-scratch projects should look at @cloudflare/think.

Examples

The examples/ directory has 30+ self-contained demos. A non-exhaustive tour:

• Showcase — playground/ is the kitchen-sink app: state, callable methods, scheduling, chat, tools, MCP, workflows, email, voice — all in one UI
• Chat & assistants — assistant/, agents-as-tools/, agent-skills/, workspace-chat/, resumable-stream-chat/, structured-input/, dynamic-tools/, multi-ai-chat/, context-overflow-recovery/
• MCP — mcp/, mcp-client/, mcp-server/, mcp-worker/, mcp-worker-authenticated/, mcp-elicitation-mrtr/, mcp-elicitation/, mcp-rpc-transport/, webmcp/, webmcp-react/
• Code Mode & sandboxes — codemode/, codemode-mcp/, codemode-mcp-openapi/, dynamic-workers/, dynamic-workers-playground/, worker-bundler-playground/
• Voice — voice-agent/ is the unified voice pipeline example with Workers AI, AssemblyAI, Telnyx, and ElevenLabs STT; voice-input/ covers dictation; telnyx-voice-agent/ covers phone transport; elevenlabs-starter/ covers broader ElevenLabs media APIs
• Workflows & approvals — workflows/, a2a/
• Auth, payments, comms — auth-agent/, channels/, cross-domain/, x402/, x402-mcp/, email-agent/, github-webhook/, push-notifications/
• Game & misc — tictactoe/, ai-chat/

Examples using the OpenAI Agents SDK live in openai-sdk/. Work-in-progress experiments live in experimental/ (no stability guarantees).

Run any example locally:

cd examples/playground
npm start

Documentation

• Full docs on developers.cloudflare.com
• docs/ directory in this repo (synced upstream)
• Anthropic Patterns guide — sequential, routing, parallel, orchestrator, evaluator
• Human-in-the-Loop guide — approval workflows with pause/resume
• design/ — architecture and design decision records (chat API, sub-agents, agent tools, workspace, voice, browser tools, retries, and more)

Repository Structure

Directory Description packages/agents/ Core SDK packages/ai-chat/ AI chat layer packages/think/ Opinionated chat agent base packages/codemode/ Code Mode packages/shell/ Sandboxed execution + filesystem packages/voice/ Deprecated Voice compatibility wrapper packages/worker-bundler/ Runtime Workers bundler packages/hono-agents/ Hono integration examples/ Self-contained demo apps experimental/ Work-in-progress experiments (not published) openai-sdk/ Examples using the OpenAI Agents SDK guides/ In-depth pattern tutorials docs/ Markdown docs synced to developers.cloudflare.com site/ Deployed websites (agents.cloudflare.com, AI playground) design/ Architecture and design decision records scripts/ Repo-wide tooling

Development

Node 24+ required. pnpm workspaces with Nx for task orchestration, caching, and affected detection.

pnpm install                 # install all workspaces
pnpm run build               # build all packages (Nx, cached, dependency-ordered)
pnpm run check               # sherif + export checks + oxfmt + oxlint + typecheck
pnpm run test                # vitest + vitest-pool-workers (Workers runtime)
pnpm run test:react          # Playwright-based React hook tests
pnpm exec nx affected -t