How to build an AI chatbot with JavaScript

npm install openai readline

import OpenAI from "openai";
import * as readline from "readline";

const client = new OpenAI({
  apiKey: "YOUR_API_KEY",
  baseURL: "https://api.acedata.cloud/v1",
});

const rl = readline.createInterface({
  input: process.stdin,
  output: process.stdout,
});

const messages = [];

async function chat() {
  console.log("Chatbot ready. Type 'quit' to exit.\n");

  const askQuestion = () => {
    rl.question("You: ", async (input) => {
      if (input.toLowerCase() === "quit") {
        rl.close();
        return;
      }

      messages.push({ role: "user", content: input });

      const stream = await client.chat.completions.create({
        model: "gpt-4o",
        messages,
        stream: true,
      });

      process.stdout.write("AI: ");
      let fullResponse = "";

      for await (const chunk of stream) {
        const content = chunk.choices[0]?.delta?.content || "";
        process.stdout.write(content);
        fullResponse += content;
      }
      console.log();

      messages.push({ role: "assistant", content: fullResponse });
      askQuestion();
    });
  };

  askQuestion();
}

chat();

// Just change the model string — same code, same API
const stream = await client.chat.completions.create({
  model: "claude-sonnet-4-20250514", // or "gpt-4o", "gemini-2.5-flash"
  messages,
  stream: true,
});