Cloudflare Think

import * as cloudflareThink from "@cloudflare/think";
import { createOpenAI } from "@ai-sdk/openai";
import { initLogger, wrapCloudflareThink } from "braintrust";
import { tool } from "ai";
import { z } from "zod";

interface Env {
  BRAINTRUST_API_KEY: string;
  OPENAI_API_KEY: string;
  THINK_AGENT: DurableObjectNamespace<MyAgent>;
}

// Wrap the module at module scope so every agent instance is instrumented
const { Think } = wrapCloudflareThink(cloudflareThink);

export class MyAgent extends Think<Env> {
  getModel() {
    return createOpenAI({ apiKey: this.env.OPENAI_API_KEY }).chat("gpt-5-mini");
  }

  getSystemPrompt() {
    return "You are a helpful weather assistant.";
  }

  getTools() {
    return {
      lookup_weather: tool({
        description: "Get the weather for a city.",
        inputSchema: z.object({ city: z.string() }),
        execute: async ({ city }) => ({ city, condition: "sunny" }),
      }),
    };
  }
}

export default {
  async fetch(request: Request, env: Env, ctx: ExecutionContext) {
    const logger = initLogger({
      projectName: "cloudflare-think-example", // Replace with your project name
      apiKey: env.BRAINTRUST_API_KEY,
    });

    try {
      const agent = env.THINK_AGENT.getByName("default");
      const result = await agent.runTurn({
        input: "What is the weather in Vienna?",
        mode: "wait",
      });
      return Response.json(result);
    } finally {
      ctx.waitUntil(logger.flush());
    }
  },
};

{
  "main": "src/cloudflare-think-manual.ts",
  "compatibility_flags": ["nodejs_compat"],
  "durable_objects": {
    "bindings": [{ "name": "THINK_AGENT", "class_name": "MyAgent" }]
  },
  "migrations": [{ "tag": "v1", "new_sqlite_classes": ["MyAgent"] }]
}