openai-sheets.js

var API_KEY = 'YOUR_API_KEY';

function runGPT() {
  var sheet = SpreadsheetApp.getActiveSheet();
  var range = sheet.getRange('A1:B1').getValues();
  var cell1 = range[0][0];
  var cell2 = range[0][1];
  var prompt = cell1 + ' space ' + cell2;
  
  var API_URL = 'https://api.openai.com/v1/completions';
  var payload = {
    'prompt': prompt,
    'model': 'text-davinci-003',
    'max_tokens': 300,
    'top_p': 1,
    'frequency_penalty': 0,
    'presence_penalty': 0
  };
  
  var response = UrlFetchApp.fetch(API_URL, {
    'method': 'post',
    'headers': {
      'Content-Type': 'application/json',
      'Authorization': 'Bearer ' + API_KEY
    },
    'payload': JSON.stringify(payload)
  });
  
  var responseText = response.getContentText();
  var responseJson = JSON.parse(responseText);
  var output = responseJson['choices'][0]['text'];
  
  sheet.getRange('C1').setValue(output);
}