fetch("https://openrouter.ai/api/v1/chat/completions", {
    method: "POST",
    headers: {
      "Authorization": "Bearer <OPENROUTER_API_KEY>",
      "HTTP-Referer": "<YOUR_SITE_URL>", // Optional. Site URL for rankings on openrouter.ai.
      "X-OpenRouter-Title": "<YOUR_SITE_NAME>", // Optional. Site title for rankings on openrouter.ai.
      "Content-Type": "application/json"
    },
    body: JSON.stringify({
      "model": "<MODEL_ID>", // Required. ex: "openai/gpt-4o",
      "messages": [
        {"role": "user", "content": "hey"}
      ]
    })
  });