# Jackspace Claudeskillz Cloudflare Agents

> Cloudflare Agents SDK

- Skill: `tomevault-io/jackspace-claudeskillz-cloudflare-agents` (Agent Skill, multi-file: 2 files)
- Install (CLI): `npx skillmds@latest add tomevault-io/jackspace-claudeskillz-cloudflare-agents`
- Raw SKILL.md: https://api.skillmd.com/api/skills/tomevault-io/jackspace-claudeskillz-cloudflare-agents/raw
- Safety review: pending (external: skill-scanner PASS, skillspector PASS)
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- Author: tomevault-io (https://skillmd.com/u/tomevault-io)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/tomevault-io/jackspace-claudeskillz-cloudflare-agents

---


# Cloudflare Agents SDK

**Status**: Production Ready ✅
**Last Updated**: 2025-10-21
**Dependencies**: cloudflare-worker-base (recommended)
**Latest Versions**: agents@latest, @modelcontextprotocol/sdk@latest
**Production Tested**: Cloudflare's own MCP servers (https://github.com/cloudflare/mcp-server-cloudflare)

---

## What is Cloudflare Agents?

The Cloudflare Agents SDK enables building AI-powered autonomous agents that run on Cloudflare Workers + Durable Objects. Agents can:

- **Communicate in real-time** via WebSockets and Server-Sent Events
- **Persist state** with built-in SQLite database (up to 1GB per agent)
- **Schedule tasks** using delays, specific dates, or cron expressions
- **Run workflows** by triggering asynchronous Cloudflare Workflows
- **Browse the web** using Browser Rendering API + Puppeteer
- **Implement RAG** with Vectorize vector database + Workers AI embeddings
- **Build MCP servers** implementing the Model Context Protocol
- **Support human-in-the-loop** patterns for review and approval
- **Scale to millions** of independent agent instances globally

Each agent instance is a **globally unique, stateful micro-server** that can run for seconds, minutes, or hours.

---

## Quick Start (10 Minutes)

### 1. Scaffold Project with Template

```bash
npm create cloudflare@latest my-agent -- \
  --template=cloudflare/agents-starter \
  --ts \
  --git \
  --deploy false
```

**What this creates:**
- Complete Agent project structure
- TypeScript configuration
- wrangler.jsonc with Durable Objects bindings
- Example chat agent implementation
- React client with useAgent hook

### 2. Or Add to Existing Worker

```bash
cd my-existing-worker
npm install agents
```

**Then create an Agent class:**

```typescript
// src/index.ts
import { Agent, AgentNamespace } from "agents";

export class MyAgent extends Agent {
  async onRequest(request: Request): Promise<Response> {
    return new Response("Hello from Agent!");
  }
}

export default MyAgent;
```

### 3. Configure Durable Objects Binding

Create or update `wrangler.jsonc`:

```jsonc
{
  "$schema": "node_modules/wrangler/config-schema.json",
  "name": "my-agent",
  "main": "src/index.ts",
  "compatibility_date": "2025-10-21",
  "compatibility_flags": ["nodejs_compat"],
  "durable_objects": {
    "bindings": [
      {
        "name": "MyAgent",        // MUST match class name
        "class_name": "MyAgent"   // MUST match exported class
      }
    ]
  },
  "migrations": [
    {
      "tag": "v1",
      "new_sqlite_classes": ["MyAgent"]  // CRITICAL: Enables SQLite storage
    }
  ]
}
```

**CRITICAL Configuration Rules:**
- ✅ `name` and `class_name` **MUST be identical**
- ✅ `new_sqlite_classes` **MUST be in first migration** (cannot add later)
- ✅ Agent class **MUST be exported** (or binding will fail)
- ✅ Migration tags **CANNOT be reused** (each migration needs unique tag)

### 4. Deploy

```bash
npx wrangler@latest deploy
```

Your agent is now running at: `https://my-agent.<subdomain>.workers.dev`

---

## Configuration Deep Dive

### Complete wrangler.jsonc Example

```jsonc
{
  "$schema": "node_modules/wrangler/config-schema.json",
  "name": "my-agent",
  "main": "src/index.ts",
  "account_id": "YOUR_ACCOUNT_ID",
  "compatibility_date": "2025-10-21",
  "compatibility_flags": ["nodejs_compat"],

  // Durable Objects configuration (REQUIRED)
  "durable_objects": {
    "bindings": [
      {
        "name": "MyAgent",
        "class_name": "MyAgent"
      }
    ]
  },

  // Migrations (REQUIRED)
  "migrations": [
    {
      "tag": "v1",
      "new_sqlite_classes": ["MyAgent"]  // Enables state persistence
    }
  ],

  // Optional: Workers AI binding (for AI model calls)
  "ai": {
    "binding": "AI"
  },

  // Optional: Vectorize binding (for RAG)
  "vectorize": {
    "bindings": [
      {
        "binding": "VECTORIZE",
        "index_name": "my-agent-vectors"
      }
    ]
  },

  // Optional: Browser Rendering binding (for web browsing)
  "browser": {
    "binding": "BROWSER"
  },

  // Optional: Workflows binding (for async workflows)
  "workflows": [
    {
      "name": "MY_WORKFLOW",
      "class_name": "MyWorkflow",
      "script_name": "my-workflow-script"  // If in different project
    }
  ],

  // Optional: D1 binding (for additional persistent data)
  "d1_databases": [
    {
      "binding": "DB",
      "database_name": "my-agent-db",
      "database_id": "your-database-id"
    }
  ],

  // Optional: R2 binding (for file storage)
  "r2_buckets": [
    {
      "binding": "BUCKET",
      "bucket_name": "my-agent-files"
    }
  ],

  // Optional: Environment variables
  "vars": {
    "ENVIRONMENT": "production"
  },

  // Optional: Secrets (set with: wrangler secret put KEY)
  // OPENAI_API_KEY, ANTHROPIC_API_KEY, etc.

  // Observability
  "observability": {
    "enabled": true
  }
}
```

### Migrations Best Practices

**Atomic Deployments**: Migrations are **atomic operations** - they cannot be gradually deployed.

```jsonc
{
  "migrations": [
    {
      "tag": "v1",
      "new_sqlite_classes": ["MyAgent"]  // Initial: enable SQLite
    },
    {
      "tag": "v2",
      "renamed_classes": [
        {"from": "MyAgent", "to": "MyRenamedAgent"}
      ]
    },
    {
      "tag": "v3",
      "deleted_classes": ["OldAgent"]
    },
    {
      "tag": "v4",
      "transferred_classes": [
        {
          "from": "AgentInOldScript",
          "from_script": "old-worker",
          "to": "AgentInNewScript"
        }
      ]
    }
  ]
}
```

**Migration Rules:**
- ✅ Each migration needs a unique `tag`
- ✅ Cannot enable SQLite on existing deployed class (must be in first migration)
- ✅ Migrations apply in order during deployment
- ✅ Cannot edit or remove previous migration tags
- ❌ Never deploy new migrations gradually (atomic only)

### Environment-Specific Migrations

```jsonc
{
  "migrations": [{"tag": "v1", "new_sqlite_classes": ["MyAgent"]}],
  "env": {
    "staging": {
      "migrations": [
        {"tag": "v1", "new_sqlite_classes": ["MyAgent"]},
        {"tag": "v2-staging", "renamed_classes": [{"from": "MyAgent", "to": "StagingAgent"}]}
      ]
    }
  }
}
```

---

## Agent Class API

The `Agent` class is the foundation of the Agents SDK. Extend it to create your agent.

### Basic Agent Structure

```typescript
import { Agent } from "agents";

interface Env {
  // Environment variables and bindings
  OPENAI_API_KEY: string;
  AI: Ai;
  VECTORIZE: Vectorize;
  DB: D1Database;
}

interface State {
  // Your agent's persistent state
  counter: number;
  messages: string[];
  lastUpdated: Date | null;
}

export class MyAgent extends Agent<Env, State> {
  // Optional: Set initial state (first time agent is created)
  initialState: State = {
    counter: 0,
    messages: [],
    lastUpdated: null
  };

  // Optional: Called when agent instance starts or wakes from hibernation
  async onStart() {
    console.log('Agent started:', this.name, 'State:', this.state);
  }

  // Handle HTTP requests
  async onRequest(request: Request): Promise<Response> {
    return Response.json({ message: "Hello from Agent", state: this.state });
  }

  // Handle WebSocket connections (optional)
  async onConnect(connection: Connection, ctx: ConnectionContext) {
    console.log('Client connected:', connection.id);
    // Connections are automatically accepted
  }

  // Handle WebSocket messages (optional)
  async onMessage(connection: Connection, message: WSMessage) {
    if (typeof message === 'string') {
      connection.send(`Echo: ${message}`);
    }
  }

  // Handle WebSocket errors (optional)
  async onError(connection: Connection, error: unknown): Promise<void> {
    console.error('Connection error:', error);
  }

  // Handle WebSocket close (optional)
  async onClose(connection: Connection, code: number, reason: string, wasClean: boolean): Promise<void> {
    console.log('Connection closed:', code, reason);
  }

  // Called when state is updated from any source (optional)
  onStateUpdate(state: State, source: "server" | Connection) {
    console.log('State updated:', state, 'Source:', source);
  }

  // Custom methods (call from any handler)
  async customMethod(data: any) {
    this.setState({
      ...this.state,
      counter: this.state.counter + 1,
      lastUpdated: new Date()
    });
  }
}
```

### Accessing Agent Properties

Within any Agent method:

```typescript
export class MyAgent extends Agent<Env, State> {
  async someMethod() {
    // Access environment variables and bindings
    const apiKey = this.env.OPENAI_API_KEY;
    const ai = this.env.AI;

    // Access current state (read-only)
    const counter = this.state.counter;

    // Update state (persisted automatically)
    this.setState({ ...this.state, counter: counter + 1 });

    // Access SQL database
    const results = await this.sql`SELECT * FROM users`;

    // Get agent instance name
    const instanceName = this.name;  // e.g., "user-123"

    // Schedule tasks
    await this.schedule(60, "runLater", { data: "example" });

    // Call other methods
    await this.customMethod({ foo: "bar" });
  }
}
```

---

## HTTP & Server-Sent Events

### HTTP Request Handling

```typescript
export class MyAgent extends Agent<Env> {
  async onRequest(request: Request): Promise<Response> {
    const url = new URL(request.url);
    const method = request.method;

    if (method === "POST" && url.pathname === "/increment") {
      const counter = (this.state.counter || 0) + 1;
      this.setState({ ...this.state, counter });
      return Response.json({ counter });
    }

    if (method === "GET" && url.pathname === "/status") {
      return Response.json({ state: this.state, name: this.name });
    }

    return new Response("Not Found", { status: 404 });
  }
}
```

### Server-Sent Events (SSE) Streaming

```typescript
export class MyAgent extends Agent<Env> {
  async onRequest(request: Request): Promise<Response> {
    const stream = new ReadableStream({
      async start(controller) {
        const encoder = new TextEncoder();

        // Send events to client
        controller.enqueue(encoder.encode('data: {"message": "Starting"}\n\n'));

        await new Promise(resolve => setTimeout(resolve, 1000));

        controller.enqueue(encoder.encode('data: {"message": "Processing"}\n\n'));

        await new Promise(resolve => setTimeout(resolve, 1000));

        controller.enqueue(encoder.encode('data: {"message": "Complete"}\n\n'));

        controller.close();
      }
    });

    return new Response(stream, {
      headers: {
        'Content-Type': 'text/event-stream',
        'Cache-Control': 'no-cache',
        'Connection': 'keep-alive'
      }
    });
  }
}
```

**SSE vs WebSockets:**

| Feature | SSE | WebSockets |
|---------|-----|------------|
| Direction | Server → Client only | Bi-directional |
| Protocol | HTTP | ws:// or wss:// |
| Reconnection | Automatic | Manual |
| Binary Data | Limited | Full support |
| Use Case | Streaming responses, notifications | Chat, real-time collaboration |

**Recommendation**: Use WebSockets for most agent applications (full duplex, better for long sessions).

---

## WebSockets

### Complete WebSocket Example

```typescript
import { Agent, Connection, ConnectionContext, WSMessage } from "agents";

interface ChatState {
  messages: Array<{ id: string; text: string; sender: string; timestamp: number }>;
  participants: string[];
}

export class ChatAgent extends Agent<Env, ChatState> {
  initialState: ChatState = {
    messages: [],
    participants: []
  };

  async onConnect(connection: Connection, ctx: ConnectionContext) {
    // Access original HTTP request for auth
    const authHeader = ctx.request.headers.get('Authorization');
    const userId = ctx.request.headers.get('X-User-ID') || 'anonymous';

    // Connections are automatically accepted
    // Optionally close connection if unauthorized:
    // if (!authHeader) {
    //   connection.close(401, "Unauthorized");
    //   return;
    // }

    // Add to participants
    this.setState({
      ...this.state,
      participants: [...this.state.participants, userId]
    });

    // Send welcome message
    connection.send(JSON.stringify({
      type: 'welcome',
      message: 'Connected to chat',
      participants: this.state.participants
    }));
  }

  async onMessage(connection: Connection, message: WSMessage) {
    if (typeof message === 'string') {
      try {
        const data = JSON.parse(message);

        if (data.type === 'chat') {
          // Add message to state
          const newMessage = {
            id: crypto.randomUUID(),
            text: data.text,
            sender: data.sender || 'anonymous',
            timestamp: Date.now()
          };

          this.setState({
            ...this.state,
            messages: [...this.state.messages, newMessage]
          });

          // Broadcast to this connection (state sync will broadcast to all)
          connection.send(JSON.stringify({
            type: 'message_added',
            message: newMessage
          }));
        }
      } catch (e) {
        connection.send(JSON.stringify({ type: 'error', message: 'Invalid message format' }));
      }
    }
  }

  async onError(connection: Connection, error: unknown): Promise<void> {
    console.error('WebSocket error:', error);
    // Optionally log to external monitoring
  }

  async onClose(connection: Connection, code: number, reason: string, wasClean: boolean): Promise<void> {
    console.log(`Connection ${connection.id} closed:`, code, reason, wasClean);
    // Clean up connection-specific state if needed
  }
}
```

### Connection Management

```typescript
export class MyAgent extends Agent {
  async onMessage(connection: Connection, message: WSMessage) {
    // Connection properties
    const connId = connection.id;  // Unique connection ID
    const connState = connection.state;  // Connection-specific state

    // Update connection state (not agent state)
    connection.setState({ ...connection.state, lastActive: Date.now() });

    // Send to this connection only
    connection.send("Message to this client");

    // Close connection programmatically
    connection.close(1000, "Goodbye");
  }
}
```

---

## State Management

### Using setState()

```typescript
interface UserState {
  name: string;
  email: string;
  preferences: { theme: string; notifications: boolean };
  loginCount: number;
  lastLogin: Date | null;
}

export class UserAgent extends Agent<Env, UserState> {
  initialState: UserState = {
    name: "",
    email: "",
    preferences: { theme: "dark", notifications: true },
    loginCount: 0,
    lastLogin: null
  };

  async onRequest(request: Request): Promise<Response> {
    if (request.method === "POST" && new URL(request.url).pathname === "/login") {
      // Update state
      this.setState({
        ...this.state,
        loginCount: this.state.loginCount + 1,
        lastLogin: new Date()
      });

      // State is automatically persisted and synced to connected clients
      return Response.json({ success: true, state: this.state });
    }

    return Response.json({ state: this.state });
  }

  onStateUpdate(state: UserState, source: "server" | Connection) {
    console.log('State updated:', state);
    console.log('Source:', source);  // "server" or Connection object

    // React to state changes
    if (state.loginCount > 10) {
      console.log('Frequent user!');
    }
  }
}
```

**State Rules:**
- ✅ State is JSON-serializable (objects, arrays, strings, numbers, booleans, null)
- ✅ State persists across agent restarts
- ✅ State is immediately consistent within the agent
- ✅ State automatically syncs to connected WebSocket clients
- ❌ State cannot contain functions or circular references
- ❌ Total state size limited by database size (1GB max per agent)

### Using SQL Database

Each agent has a built-in SQLite database accessible via `this.sql`:

```typescript
export class MyAgent extends Agent {
  async onStart() {
    // Create tables on first start
    await this.sql`
      CREATE TABLE IF NOT EXISTS users (
        id INTEGER PRIMARY KEY AUTOINCREMENT,
        name TEXT NOT NULL,
        email TEXT UNIQUE NOT NULL,
        created_at DATETIME DEFAULT CURRENT_TIMESTAMP
      )
    `;

    await this.sql`
      CREATE INDEX IF NOT EXISTS idx_email ON users(email)
    `;
  }

  async addUser(name: string, email: string) {
    // Insert with prepared statement (prevents SQL injection)
    const result = await this.sql`
      INSERT INTO users (name, email)
      VALUES (${name}, ${email})
    `;

    return result;
  }

  async getUser(email: string) {
    // Query returns array of results
    const users = await this.sql`
      SELECT * FROM users WHERE email = ${email}
    `;

    return users[0] || null;
  }

  async getAllUsers() {
    const users = await this.sql`
      SELECT * FROM users ORDER BY created_at DESC
    `;

    return users;
  }

  async updateUser(id: number, name: string) {
    await this.sql`
      UPDATE users SET name = ${name} WHERE id = ${id}
    `;
  }

  async deleteUser(id: number) {
    await this.sql`
      DELETE FROM users WHERE id = ${id}
    `;
  }
}
```

**SQL Best Practices:**
- ✅ Use tagged template literals (prevents SQL injection)
- ✅ Create indexes for frequently queried columns
- ✅ Use transactions for multiple related operations
- ✅ Query results are always arrays (even for single row)
- ❌ Don't construct SQL strings manually
- ❌ Be mindful of 1GB database size limit

---

## Schedule Tasks

Agents can schedule tasks to run in the future using `this.schedule()`.

### Delay (Seconds)

```typescript
export class MyAgent extends Agent {
  async onRequest(request: Request): Promise<Response> {
    // Schedule task to run in 60 seconds
    const { id } = await this.schedule(60, "checkStatus", { requestId: "123" });

    return Response.json({ scheduledTaskId: id });
  }

  // This method will be called in 60 seconds
  async checkStatus(data: { requestId: string }) {
    console.log('Checking status for request:', data.requestId);
    // Perform check, update state, send notification, etc.
  }
}
```

### Specific Date

```typescript
export class MyAgent extends Agent {
  async scheduleReminder(reminderDate: string) {
    const date = new Date(reminderDate);

    const { id } = await this.schedule(date, "sendReminder", {
      message: "Time for your appointment!"
    });

    return id;
  }

  async sendReminder(data: { message: string }) {
    console.log('Sending reminder:', data.message);
    // Send email, push notification, etc.
  }
}
```

### Cron Expressions

```typescript
export class MyAgent extends Agent {
  async setupRecurringTasks() {
    // Every 10 minutes
    await this.schedule("*/10 * * * *", "checkUpdates", {});

    // Every day at 8 AM
    await this.schedule("0 8 * * *", "dailyReport", {});

    // Every Monday at 9 AM
    await this.schedule("0 9 * * 1", "weeklyReport", {});

    // Every hour on the hour
    await this.schedule("0 * * * *", "hourlyCheck", {});
  }

  async checkUpdates(data: any) {
    console.log('Checking for updates...');
  }

  async dailyReport(data: any) {
    console.log('Generating daily report...');
  }

  async weeklyReport(data: any) {
    console.log('Generating weekly report...');
  }

  async hourlyCheck(data: any) {
    console.log('Running hourly check...');
  }
}
```

### Managing Scheduled Tasks

```typescript
export class MyAgent extends Agent {
  async manageSchedules() {
    // Get all scheduled tasks
    const allTasks = this.getSchedules();
    console.log('Total tasks:', allTasks.length);

    // Get specific task by ID
    const taskId = "some-task-id";
    const task = await this.getSchedule(taskId);

    if (task) {
      console.log('Task:', task.callback, 'at', new Date(task.time));
      console.log('Payload:', task.payload);
      console.log('Type:', task.type);  // "scheduled" | "delayed" | "cron"

      // Cancel the task
      const cancelled = await this.cancelSchedule(taskId);
      console.log('Cancelled:', cancelled);
    }

    // Get tasks in time range
    const upcomingTasks = this.getSchedules({
      timeRange: {
        start: new Date(),
        end: new Date(Date.now() + 24 * 60 * 60 * 1000)  // Next 24 hours
      }
    });

    console.log('Upcoming tasks:', upcomingTasks.length);

    // Filter by type
    const cronTasks = this.getSchedules({ type: "cron" });
    const delayedTasks = this.getSchedules({ type: "delayed" });
  }
}
```

**Scheduling Constraints:**
- Each task maps to a SQL database row (max 2 MB per task)
- Total tasks limited by: `(task_size * count) + other_state < 1GB`
- Cron tasks continue running until explicitly cancelled
- Callback method MUST exist on Agent class (throws error if missing)

**CRITICAL ERROR**: If callback method doesn't exist:
```typescript
// ❌ BAD: Method doesn't exist
await this.schedule(60, "nonExistentMethod", {});

// ✅ GOOD: Method exists
await this.schedule(60, "existingMethod", {});

async existingMethod(data: any) {
  // Implementation
}
```

---

## Run Workflows

Agents can trigger asynchronous [Cloudflare Workflows](https://developers.cloudflare.com/workflows/).

### Workflow Binding Configuration

`wrangler.jsonc`:

```jsonc
{
  "workflows": [
    {
      "name": "MY_WORKFLOW",
      "class_name": "MyWorkflow"
    }
  ]
}
```

If Workflow is in a different script:

```jsonc
{
  "workflows": [
    {
      "name": "EMAIL_WORKFLOW",
      "class_name": "EmailWorkflow",
      "script_name": "email-workflows"  // Different project
    }
  ]
}
```

### Triggering a Workflow

```typescript
import { Agent } from "agents";
import { WorkflowEntrypoint, WorkflowEvent, WorkflowStep } from "cloudflare:workers";

interface Env {
  MY_WORKFLOW: Workflow;
  MyAgent: AgentNamespace<MyAgent>;
}

export class MyAgent extends Agent<Env> {
  async onRequest(request: Request): Promise<Response> {
    const userId = new URL(request.url).searchParams.get('userId');

    // Trigger a workflow immediately
    const instance = await this.env.MY_WORKFLOW.create({
      id: `user-${userId}`,
      params: { userId, action: "process" }
    });

    // Or schedule a delayed workflow trigger
    await this.schedule(300, "runWorkflow", { userId });

    return Response.json({ workflowId: instance.id });
  }

  async runWorkflow(data: { userId: string }) {
    const instance = await this.env.MY_WORKFLOW.create({
      id: `delayed-${data.userId}`,
      params: data
    });

    // Monitor workflow status periodically
    await this.schedule("*/5 * * * *", "checkWorkflowStatus", { id: instance.id });
  }

  async checkWorkflowStatus(data: { id: string }) {
    // Check workflow status (see Workflows docs for details)
    console.log('Checking workflow:', data.id);
  }
}

// Workflow definition (can be in same or different file/project)
export class MyWorkflow extends WorkflowEntrypoint<Env> {
  async run(event: WorkflowEvent<{ userId: string }>, step: WorkflowStep) {
    // Workflow implementation
    const result = await step.do('process-data', async () => {
      return { processed: true };
    });

    return result;
  }
}
```

### Agents vs Workflows

| Feature | Agents | Workflows |
|---------|--------|-----------|
| **Purpose** | Interactive, user-facing | Background processing |
| **Duration** | Seconds to hours | Minutes to hours |
| **State** | SQLite database | Step-based checkpoints |
| **Interaction** | WebSockets, HTTP | No direct interaction |
| **Retry** | Manual | Automatic per step |
| **Use Case** | Chat, real-time UI | ETL, batch processing |

**Best Practice**: Use Agents to **coordinate** multiple Workflows. Agents can trigger, monitor, and respond to Workflow results while maintaining user interaction.

---

## Browse the Web

Agents can browse the web using [Browser Rendering](https://developers.cloudflare.com/browser-rendering/).

### Browser Rendering Binding

`wrangler.jsonc`:

```jsonc
{
  "browser": {
    "binding": "BROWSER"
  }
}
```

### Installation

```bash
npm install @cloudflare/puppeteer
```

### Web Scraping Example

```typescript
import { Agent } from "agents";
import puppeteer from "@cloudflare/puppeteer";

interface Env {
  BROWSER: Fetcher;
  OPENAI_API_KEY: string;
}

export class BrowserAgent extends Agent<Env> {
  async browse(urls: string[]) {
    const responses = [];

    for (const url of urls) {
      const browser = await puppeteer.launch(this.env.BROWSER);
      const page = await browser.newPage();

      await page.goto(url);
      await page.waitForSelector("body");

      const bodyContent = await page.$eval("body", el => el.innerHTML);

      // Extract data with AI
      const data = await this.extractData(bodyContent);
      responses.push({ url, data });

      await browser.close();
    }

    return responses;
  }

  async extractData(html: string): Promise<any> {
    // Use OpenAI or Workers AI to extract structured data
    const response = await fetch('https://api.openai.com/v1/chat/completions', {
      method: 'POST',
      headers: {
        'Authorization': `Bearer ${this.env.OPENAI_API_KEY}`,
        'Content-Type': 'application/json'
      },
      body: JSON.stringify({
        model: 'gpt-4o-mini',
        messages: [{
          role: 'user',
          content: `Extract product info from HTML: ${html.slice(0, 4000)}`
        }],
        response_format: { type: "json_object" }
      })
    });

    const result = await response.json();
    return JSON.parse(result.choices[0].message.content);
  }

  async onRequest(request: Request): Promise<Response> {
    const url = new URL(request.url).searchParams.get('url');
    if (!url) {
      return new Response("Missing url parameter", { status: 400 });
    }

    const results = await this.browse([url]);
    return Response.json(results);
  }
}
```

### Screenshot Capture

```typescript
export class ScreenshotAgent extends Agent<Env> {
  async captureScreenshot(url: string): Promise<Buffer> {
    const browser = await puppeteer.launch(this.env.BROWSER);
    const page = await browser.newPage();

    await page.goto(url);
    const screenshot = await page.screenshot({ fullPage: true });

    await browser.close();

    return screenshot;
  }
}
```

---

## Retrieval Augmented Generation (RAG)

Implement RAG using Vectorize + Workers AI embeddings.

### Vectorize Binding

`wrangler.jsonc`:

```jsonc
{
  "ai": {
    "binding": "AI"
  },
  "vectorize": {
    "bindings": [
      {
        "binding": "VECTORIZE",
        "index_name": "my-agent-vectors"
      }
    ]
  }
}
```

### Create Index

```bash
npx wrangler vectorize create my-agent-vectors \
  --dimensions=768 \
  --metric=cosine
```

### Complete RAG Implementation

```typescript
import { Agent } from "agents";
import { generateText } from "ai";
import { openai } from "@ai-sdk/openai";

interface Env {
  AI: Ai;
  VECTORIZE: Vectorize;
  OPENAI_API_KEY: string;
}

export class RAGAgent extends Agent<Env> {
  // Ingest documents
  async ingestDocuments(documents: Array<{ id: string; text: string; metadata: any }>) {
    const vectors = [];

    for (const doc of documents) {
      // Generate embedding with Workers AI
      const { data } = await this.env.AI.run('@cf/baai/bge-base-en-v1.5', {
        text: [doc.text]
      });

      vectors.push({
        id: doc.id,
        values: data[0],
        metadata: { ...doc.metadata, text: doc.text }
      });
    }

    // Insert into Vectorize
    await this.env.VECTORIZE.upsert(vectors);

    return { ingested: vectors.length };
  }

  // Query knowledge base
  async queryKnowledge(userQuery: string, topK: number = 5) {
    // Generate query embedding
    const { data } = await this.env.AI.run('@cf/baai/bge-base-en-v1.5', {
      text: [userQuery]
    });

    // Search Vectorize
    const results = await this.env.VECTORIZE.query(data[0], { topK });

    // Extract relevant documents
    const context = results.matches.map(match => match.metadata.text).join('\n\n');

    return context;
  }

  // RAG Chat
  async chat(userMessage: string) {
    // Retrieve relevant context
    const context = await this.queryKnowledge(userMessage);

    // Generate response with context
    const { text } = await generateText({
      model: openai('gpt-4o-mini'),
      messages: [
        {
          role: 'system',
          content: `You are a helpful assistant. Use the following context to answer questions:\n\n${context}`
        },
        {
          role: 'user',
          content: userMessage
        }
      ]
    });

    return { response: text, context };
  }

  async onRequest(request: Request): Promise<Response> {
    const { message } = await request.json();
    const result = await this.chat(message);
    return Response.json(result);
  }
}
```

### Metadata Filtering

```typescript
// Create metadata indexes BEFORE inserting vectors
await this.env.VECTORIZE.createMetadataIndex("category");
await this.env.VECTORIZE.createMetadataIndex("language");

// Query with filters
const results = await this.env.VECTORIZE.query(queryVector, {
  topK: 10,
  filter: {
    category: { $eq: "documentation" },
    language: { $eq: "en" }
  }
});
```

**See**: [cloudflare-vectorize skill](../cloudflare-vectorize/) for complete Vectorize guide.

---

## Using AI Models

### AI SDK (Vercel)

```bash
npm install ai @ai-sdk/openai @ai-sdk/anthropic
```

```typescript
import { Agent } from "agents";
import { generateText, streamText } from "ai";
import { openai } from "@ai-sdk/openai";
import { anthropic } from "@ai-sdk/anthropic";

export class AIAgent extends Agent {
  // Simple text generation
  async generateResponse(prompt: string) {
    const { text } = await generateText({
      model: openai('gpt-4o-mini'),
      prompt
    });

    return text;
  }

  // Streaming response
  async streamResponse(prompt: string): Promise<Response> {
    const result = streamText({
      model: anthropic('claude-sonnet-4-5'),
      prompt
    });

    return result.toTextStreamResponse();
  }

  // Structured output
  async extractData(text: string) {
    const { object } = await generateObject({
      model: openai('gpt-4o-mini'),
      schema: z.object({
        name: z.string(),
        email: z.string().email(),
        age: z.number().optional()
      }),
      prompt: `Extract user info from: ${text}`
    });

    return object;
  }
}
```

### Workers AI

```typescript
interface Env {
  AI: Ai;
}

export class WorkersAIAgent extends Agent<Env> {
  async generateText(prompt: string) {
    const response = await this.env.AI.run('@cf/meta/llama-3-8b-instruct', {
      messages: [{ role: 'user', content: prompt }]
    });

    return response;
  }

  async generateImage(prompt: string) {
    const response = await this.env.AI.run('@cf/black-forest-labs/flux-1-schnell', {
      prompt
    });

    return response;
  }
}
```

**See**: [cloudflare-workers-ai skill](../cloudflare-workers-ai/) for complete Workers AI guide.

---

## Calling Agents

### Using routeAgentRequest

Automatically route requests to agents based on URL pattern `/agents/:agent/:name`:

```typescript
import { Agent, AgentNamespace, routeAgentRequest } from 'agents';

interface Env {
  MyAgent: AgentNamespace<MyAgent>;
}

export default {
  async fetch(request: Request, env: Env): Promise<Response> {
    // Routes to: /agents/my-agent/user-123
    const response = await routeAgentRequest(request, env);

    if (response) {
      return response;
    }

    return new Response("Not Found", { status: 404 });
  }
} satisfies ExportedHandler<Env>;

export class MyAgent extends Agent<Env> {
  async onRequest(request: Request): Promise<Response> {
    return Response.json({ agent: this.name });
  }
}
```

**URL Pattern**: `/agents/my-agent/user-123`
- `my-agent` = class name in kebab-case
- `user-123` = agent instance name

### Using getAgentByName

For custom routing or calling agents from Workers:

```typescript
import { Agent, AgentNamespace, getAgentByName } from 'agents';

interface Env {
  MyAgent: AgentNamespace<MyAgent>;
}

export default {
  async fetch(request: Request, env: Env): Promise<Response> {
    const userId = new URL(request.url).searchParams.get('userId') || 'anonymous';

    // Get or create agent instance
    const agent = getAgentByName<Env, MyAgent>(env.MyAgent, `user-${userId}`);

    // Pass request to agent
    return (await agent).fetch(request);
  }
} satisfies ExportedHandler<Env>;

export class MyAgent extends Agent<Env> {
  // Agent implementation
}
```

### Calling Agent Methods Directly

```typescript
export default {
  async fetch(request: Request, env: Env): Promise<Response> {
    const agent = getAgentByName<Env, MyAgent>(env.MyAgent, 'user-123');

    // Call custom methods on agent using RPC
    const result = await (await agent).customMethod({ data: "example" });

    return Response.json({ result });
  }
}

export class MyAgent extends Agent<Env> {
  async customMethod(params: { data: string }): Promise<any> {
    return { processed: params.data };
  }
}
```

### Multi-Agent Communication

```typescript
interface Env {
  AgentA: AgentNamespace<AgentA>;
  AgentB: AgentNamespace<AgentB>;
}

export class AgentA extends Agent<Env> {
  async processData(data: any) {
    // Call another agent
    const agentB = getAgentByName<Env, AgentB>(this.env.AgentB, 'processor-1');
    const result = await (await agentB).analyze(data);

    return result;
  }
}

export class AgentB extends Agent<Env> {
  async analyze(data: any) {
    return { analyzed: true, data };
  }
}
```

### Authentication Patterns

```typescript
export default {
  async fetch(request: Request, env: Env): Promise<Response> {
    // Authenticate BEFORE invoking agent
    const authHeader = request.headers.get('Authorization');
    if (!authHeader) {
      return new Response("Unauthorized", { status: 401 });
    }

    const userId = await verifyToken(authHeader);
    if (!userId) {
      return new Response("Forbidden", { status: 403 });
    }

    // Only create/access agent for authenticated users
    const agent = getAgentByName<Env, MyAgent>(env.MyAgent, `user-${userId}`);
    return (await agent).fetch(request);
  }
}
```

**CRITICAL**: Always authenticate in Worker, **NOT** in Agent. Agents should assume the caller is authorized.

---

## Client APIs

### AgentClient (Browser)

```typescript
import { AgentClient } from "agents/client";

// Connect to agent instance
const client = new AgentClient({
  agent: "chat-agent",        // Class name in kebab-case
  name: "room-123",           // Instance name
  host: window.location.host
});

client.onopen = () => {
  console.log("Connected");
  client.send(JSON.stringify({ type: "join", user: "alice" }));
};

client.onmessage = (event) => {
  const data = JSON.parse(event.data);
  console.log("Received:", data);
};

client.onclose = () => {
  console.log("Disconnected");
};
```

### agentFetch (HTTP Requests)

```typescript
import { agentFetch } from "agents/client";

async function getData() {
  const response = await agentFetch(
    { agent: "my-agent", name: "user-123" },
    {
      method: "GET",
      headers: { "Authorization": `Bearer ${token}` }
    }
  );

  const data = await response.json();
  return data;
}
```

### useAgent Hook (React)

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

function ChatUI() {
  const [messages, setMessages] = useState([]);

  const connection = useAgent({
    agent: "chat-agent",
    name: "room-123",
    onMessage: (event) => {
      const data = JSON.parse(event.data);
      if (data.type === 'message') {
        setMessages(prev => [...prev, data.message]);
      }
    },
    onOpen: () => console.log("Connected"),
    onClose: () => console.log("Disconnected")
  });

  const sendMessage = (text: string) => {
    connection.send(JSON.stringify({ type: 'chat', text }));
  };

  return (
    <div>
      {messages.map((msg, i) => <div key={i}>{msg.text}</div>)}
      <button onClick={() => sendMessage("Hello")}>Send</button>
    </div>
  );
}
```

### State Synchronization

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

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

  const agent = useAgent({
    agent: "counter-agent",
    name: "my-counter",
    onStateUpdate: (newState) => {
      setCount(newState.counter);
    }
  });

  const increment = () => {
    agent.setState({ counter: count + 1 });
  };

  return (
    <div>
      <p>Count: {count}</p>
      <button onClick={increment}>Increment</button>
    </div>
  );
}
```

### useAgentChat Hook

```typescript
import { useAgentChat } from "agents/ai-react";

function ChatInterface() {
  const { messages, input, handleInputChange, handleSubmit, isLoading } = useAgentChat({
    agent: "ai-chat-agent",
    name: "chat-session-123"
  });

  return (
    <div>
      <div>
        {messages.map((msg, i) => (
          <div key={i}>
            <strong>{msg.role}:</strong> {msg.content}
          </div>
        ))}
      </div>

      <form onSubmit={handleSubmit}>
        <input
          value={input}
          onChange={handleInputChange}
          placeholder="Type a message..."
          disabled={isLoading}
        />
        <button type="submit" disabled={isLoading}>
          {isLoading ? "Thinking..." : "Send"}
        </button>
      </form>
    </div>
  );
}
```

---

## Model Context Protocol (MCP)

Build MCP servers using the Agents SDK.

### MCP Server Setup

```bash
npm install @modelcontextprotocol/sdk agents
```

### Basic MCP Server

```typescript
import { McpAgent } from "agents/mcp";
import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
import { z } from "zod";

export class MyMCP extends McpAgent {
  server = new McpServer({ name: "Demo", version: "1.0.0" });

  async init() {
    // Define a tool
    this.server.tool(
      "add",
      "Add two numbers together",
      {
        a: z.number().describe("First number"),
        b: z.number().describe("Second number")
      },
      async ({ a, b }) => ({
        content: [{ type: "text", text: String(a + b) }]
      })
    );
  }
}
```

### Stateful MCP Server

```typescript
type State = { counter: number };

export class StatefulMCP extends McpAgent<Env, State> {
  server = new McpServer({ name: "Counter", version: "1.0.0" });

  initialState: State = { counter: 0 };

  async init() {
    // Resource
    this.server.resource(
      "counter",
      "mcp://resource/counter",
      (uri) => ({
        contents: [{ uri: uri.href, text: String(this.state.counter) }]
      })
    );

    // Tool
    this.server.tool(
      "increment",
      "Increment the counter",
      { amount: z.number() },
      async ({ amount }) => {
        this.setState({
          ...this.state,
          counter: this.state.counter + amount
        });

        return {
          content: [{
            type: "text",
            text: `Counter is now ${this.state.counter}`
          }]
        };
      }
    );
  }
}
```

### MCP Transport Configuration

```typescript
import { Hono } from 'hono';

const app = new Hono();

// Modern streamable HTTP transport (recommended)
app.mount('/mcp', MyMCP.serve('/mcp').fetch, { replaceRequest: false });

// Legacy SSE transport (deprecated)
app.mount('/sse', MyMCP.serveSSE('/sse').fetch, { replaceRequest: false });

export default app;
```

**Transport Comparison:**
- **/mcp**: Streamable HTTP (modern, recommended)
- **/sse**: Server-Sent Events (legacy, deprecated)

### MCP with OAuth

```typescript
import { OAuthProvider } from '@cloudflare/workers-oauth-provider';

export default new OAuthProvider({
  apiHandlers: {
    '/sse': MyMCP.serveSSE('/sse'),
    '/mcp': MyMCP.serve('/mcp')
  },
  // OAuth configuration
  clientId: 'your-client-id',
  clientSecret: 'your-client-secret',
  // ... other OAuth settings
});

…(truncated)