Create a Google Sheets `=GPT("...")` function with your OpenAI API Key

script.js

// Source: https://jonathanboshoff.com/free-gpt-4-sheets-alternative/
function GPT(Input) {
  const GPT_API = "AAAAAAAAAAAAA";  // Replace with your actual API key
  const BASE_URL = "https://api.openai.com/v1/chat/completions";
 
  const headers = {
    "Content-Type": "application/json",
    "Authorization": `Bearer ${GPT_API}`
  };
 
  const options = {
    headers,
    method: "POST",
    muteHttpExceptions: true,
    payload: JSON.stringify({
      "model": "gpt-4o",
      "messages": [
        {
          "role": "system",
          "content": "You are a helpful assistant powered by OpenAI's GPT-4o model."
        },
        {
          "role": "user",
          "content": Input
        }
      ],
      "temperature": 0.8,
      "top_p": 1,
      "frequency_penalty": 0,
      "presence_penalty": 0
    })
  };
 
  try {
    const response = UrlFetchApp.fetch(BASE_URL, options);
    const responseJson = JSON.parse(response.getContentText());
 
    Logger.log(responseJson);  // Log the entire response for debugging
 
    if (responseJson.error) {
      Logger.log("Error from OpenAI: " + responseJson.error.message);
      return "Error: " + responseJson.error.message;
    } else {
      // Check the model used in the response
      if (responseJson.model && responseJson.model.startsWith("gpt-4")) {
        return responseJson.choices && responseJson.choices.length > 0 ? responseJson.choices[0].message.content : "No response";
      } else {
        return "Error: The response is not from the GPT-4 model.";
      }
    }
  } catch (e) {
    Logger.log("Error: " + e.message);
    return "Error: " + e.message;
  }
}