Codemode

{
  "worker_loaders": [{ "binding": "LOADER" }],
  "compatibility_flags": ["nodejs_compat"]
}

npm install @cloudflare/codemode ai zod

import { createCodeTool } from "@cloudflare/codemode/ai";
import { DynamicWorkerExecutor } from "@cloudflare/codemode";
import { streamText, tool, convertToModelMessages } from "ai";
import { z } from "zod";

const tools = {
  getWeather: tool({
    description: "Get weather for a location",
    inputSchema: z.object({ location: z.string() }),
    execute: async ({ location }) => `Weather: ${location} 72°F`
  }),
  sendEmail: tool({
    description: "Send an email",
    inputSchema: z.object({ to: z.string(), subject: z.string(), body: z.string() }),
    execute: async ({ to, subject, body }) => `Email sent to ${to}`
  })
};

export class MyAgent extends Agent<Env, State> {
  async onChatMessage() {
    const executor = new DynamicWorkerExecutor({
      loader: this.env.LOADER
    });

    const codemode = createCodeTool({ tools, executor });

    const result = streamText({
      model,
      system: "You are a helpful assistant.",
      messages: await convertToModelMessages(this.messages),
      tools: { codemode }
    });

    return result.toUIMessageStreamResponse();
  }
}

const codemode = createCodeTool({
  tools: {
    ...myTools,
    ...this.mcp.getAITools()
  },
  executor
});

const executor = new DynamicWorkerExecutor({
  loader: env.LOADER,
  globalOutbound: null           // default — fully isolated
  // globalOutbound: env.MY_SERVICE  // route through a Fetcher
});