Colador de Prova usando GPT-4o Vision e NodeJs

Colador.js

const TelegramBot = require("node-telegram-bot-api");
const OPENAI_TOKEN = "openai_token";
const TELEGRAM_TOKEN = "telegram_token";
const bot = new TelegramBot(TELEGRAM_TOKEN, { polling: true });

bot.on("message", async msg => {
	bot.sendMessage(msg.chat.id, "Pensando...");
	
	if (msg.photo) {
		const link = await bot.getFileLink(msg.photo[msg.photo.length-1].file_id);
		bot.sendMessage(msg.chat.id, await chatgpt(link));
	}
	else {
		bot.sendMessage(msg.chat.id, await chatgpt(msg.text));
	}
});

async function chatgpt(prompt) {
	if (typeof(prompt) != "string") return null;
	
	let isString;
	try {
		new URL(prompt);
		isString = false;
	}
	catch (e) {
		isString = true;
	}
	
	let r = await fetch("https://api.openai.com/v1/chat/completions", {
		method: "POST",
		headers: {
			"Content-Type": "application/json",
			"Authorization": `Bearer ${OPENAI_TOKEN}`
		},
		body: JSON.stringify({
			model: "gpt-4o",
			temperature: 0,
			messages: [
				{ role: "system", content: "Responda brevemente a seguinte questão:"},
				{ role: "user", content: [
					{
						type: isString ? "text" : "image_url",
						[isString ? "text" : "image_url"]: isString ? prompt : ({ "url" : prompt })
					}
				]}
			]
		})
	});
	
	if (r.status != 200) {
		r = await r.json();
		return r.error.message;
	}
	
	r = await r.json();
	return r.choices[0].message.content;
}