docs: update README.md

README.md

@@ -9,7 +9,49 @@
 
 ## Usage
 
-### Node.js
+### In your code
+
+```ts
+// @file: index.llama.ts
+export function getWeather(city: string) {
+  return `The weather in ${city} is sunny.`
+}
+export function getTemperature(city: string) {
+  return `The temperature in ${city} is 25°C.`
+}
+export function getCurrentCity() {
+  return 'New York'
+}
+// @file: app.ts
+import Tools from './index.llama'
+import { registerTools, convertTools } from '@llamaindex/tool'
+// Register tools on top level
+registerTools(Tools)
+
+import { OpenAI } from 'openai'
+const openai = new OpenAI()
+openai.chat.completions.create({
+  messages: [
+    {
+      role: 'user',
+      content: 'What is the weather in the current city?'
+    }
+  ],
+  tools: convertTools('openai')
+})
+
+// or you can use llamaindex openai agent
+import { OpenAIAgent } from 'llamaindex'
+const agent = new OpenAIAgent({
+  tools: convertTools('llamaindex')
+})
+const { response } = await agent.chat({
+  message: 'What is the temperature in the current city?'
+})
+console.log('Response:', response)
+```
+
+### Run with Node.js
 
 ```shell
 node --import tsx --import @llamaindex/tool/register ./app.ts