SuperAPI AI Directory
Partner中文AI newsFavorites
Skillsagents-sdk

agents-sdk

Agents & models

View repository

Updated 10-16 09:30

About this skill

Cloudflare Agents SDK

Your knowledge of the Agents SDK may be outdated. Prefer retrieval over pre-training for any Agents SDK task.

Retrieval Sources

Cloudflare docs: https://developers.cloudflare.com/agents/

Topic Docs URL Use for
Getting started Quick start First agent, project setup
Adding to existing project Add to existing project Install into existing Workers app
Configuration Configuration wrangler.jsonc, bindings, assets, deployment
Agent class Agents API Agent lifecycle, patterns, pitfalls
State Store and sync state setState, validateStateChange, persistence
Routing Routing URL patterns, routeAgentRequest
Callable methods Callable methods @callable, RPC, streaming, timeouts
Scheduling Schedule tasks schedule(), scheduleEvery(), cron
Workflows Run workflows AgentWorkflow, durable multi-step tasks
HTTP/WebSockets WebSockets Lifecycle hooks, hibernation
Chat agents Chat agents AIChatAgent, streaming, tools, persistence
Client SDK Client SDK useAgent, useAgentChat, React hooks
Client tools Client tools Client-side tools, autoContinueAfterToolResult
Server-driven messages Trigger patterns saveMessages, waitUntilStable, server-initiated turns
Resumable streaming Resumable streaming Stream recovery on disconnect
Email Email Email routing, secure reply resolver
MCP client MCP client Connecting to MCP servers
MCP server MCP server Building new servers with createMcpHandler; migrating legacy McpAgent deployments
MCP transports MCP transports Streamable HTTP, SSE, RPC transport options
Securing MCP servers Securing MCP OAuth, proxy MCP, hardening
Human-in-the-loop Human-in-the-loop Approval flows, needsApproval, workflows
Durable execution Durable execution runFiber(), stash(), surviving DO eviction
Queue Queue Built-in FIFO queue, queue()
Retries Retries this.retry(), backoff/jitter
Observability Observability Diagnostics-channel events
Push notifications Push notifications Web Push + VAPID from agents
Webhooks Webhooks Receiving external webhooks
Cross-domain auth Cross-domain auth WebSocket auth, tokens, CORS
Readonly connections Readonly shouldConnectionBeReadonly
Voice Voice Experimental STT/TTS, withVoice
Browse the web Browser tools Experimental CDP browser automation
Think Think Experimental higher-level chat agent class
Migrations AI SDK v5, AI SDK v6 Upgrading @cloudflare/ai-chat

Capabilities

The Agents SDK provides:

  • Persistent state — SQLite-backed, auto-synced to clients via setState
  • Callable RPC — @callable() methods invoked over WebSocket
  • Scheduling — One-time, recurring (scheduleEvery), and cron tasks
  • Workflows — Durable multi-step background processing via AgentWorkflow
  • Durable execution — runFiber() / stash() for work that survives DO eviction
  • Queue — Built-in FIFO queue with retries via queue()
  • Retries — this.retry() with exponential backoff and jitter
  • MCP integration — Connect to MCP servers or build stateless servers with createMcpHandler; retain McpAgent only for legacy stateful deployments
  • Email handling — Receive and reply to emails with secure routing
  • Streaming chat — AIChatAgent with resumable streams, message persistence, tools
  • Server-driven messages — saveMessages, waitUntilStable for proactive agent turns
  • React hooks — useAgent, useAgentChat for client apps
  • Observability — diagnostics_channel events for state, RPC, schedule, lifecycle
  • Push notifications — Web Push + VAPID delivery from agents
  • Webhooks — Receive and verify external webhooks
  • Voice (experimental) — STT/TTS via @cloudflare/voice
  • Browser tools (experimental) — CDP-powered browsing via agents/browser
  • Think (experimental) — Higher-level chat agent via @cloudflare/think

Check the project before implementation

Inspect the manifest, lockfile, installed version, and existing package manager. For documentation questions or reviews, use these and the matching official docs without installing dependencies. Install missing packages only as part of authorized implementation; use the repository's package manager and version policy. The npm commands below are examples for npm projects.

For a project that needs the SDK:

npm install agents

For chat agents:

npm install agents @cloudflare/ai-chat ai @ai-sdk/react

Wrangler Configuration

{
  "compatibility_flags": ["nodejs_compat"],
  "durable_objects": {
    "bindings": [{ "name": "MyAgent", "class_name": "MyAgent" }]
  },
  "exports": { "MyAgent": { "type": "durable-object", "storage": "sqlite" } }
}

Gotchas:

  • Do NOT enable experimentalDecorators in tsconfig (breaks @callable)
  • Use exports for new deployments. Existing migration-based deployments remain supported; do not add exports alongside migrations
  • Each agent class needs its own Durable Object binding and lifecycle entry in exports
  • Add "ai": { "binding": "AI" } for Workers AI

Agent Class

import { Agent, routeAgentRequest, callable, type Connection } from "agents";

type State = { count: number };

export class Counter extends Agent<Env, State> {
  initialState = { count: 0 };

  validateStateChange(nextState: State, source: Connection | "server") {
    if (nextState.count < 0) throw new Error("Count cannot be negative");
  }

  onStateChanged(state: State, source: Connection | "server") {
    console.log("State updated:", state);
  }

  @callable()
  increment() {
    this.setState({ count: this.state.count + 1 });
    return this.state.count;
  }
}

export default {
  async fetch(req, env) {
    return (await routeAgentRequest(req, env)) ?? new Response("Not found", { status: 404 });
  }
};

Routing

Requests route to /agents/{agent-name}/{instance-name}:

Class URL
Counter /agents/counter/user-123
ChatRoom /agents/chat-room/lobby

Client: useAgent({ agent: "Counter", name: "user-123" })

Custom routing: use getAgentByName(env.MyAgent, "instance-id") then agent.fetch(request).

Core APIs

Task API
Read state this.state.count
Write state this.setState({ count: 1 })
SQL query this.sql`SELECT * FROM users WHERE id = ${id}`
Schedule (delay) await this.schedule(60, "task", payload)
Schedule (cron) await this.schedule("0 * * * *", "task", payload)
Schedule (interval) await this.scheduleEvery(30, "poll")
RPC method @callable() myMethod() { ... }
Streaming RPC @callable({ streaming: true }) stream(res) { ... }
Start workflow await this.runWorkflow("PROCESSING_WORKFLOW", params)
Durable fiber await this.runFiber("name", async (ctx) => { ... })
Enqueue work this.queue("handler", payload)
Retry with backoff await this.retry(fn, { maxAttempts: 5 })
Broadcast to clients this.broadcast(message)
Get connections this.getConnections(tag?)

React Client

import { useState } from "react";
import { useAgent } from "agents/react";

function App() {
  const [state, setLocalState] = useState({ count: 0 });

  const agent = useAgent<State>({
    agent: "Counter",
    name: "my-instance",
    onStateUpdate: (newState) => setLocalState(newState),
    onIdentity: (name, agentType) => console.log(`Connected to ${name}`)
  });

  return (
    <button onClick={() => agent.setState({ count: state.count + 1 })}>
      Count: {state.count}
    </button>
  );
}

References

Core

Chat & Streaming

Background Processing

Integrations

Experimental