headless.js

function getProducts() {
  var url = "url.com/children";
  var options = {
    "method" : "get",
    "contentType": "application/json"
  };
  
  var response = UrlFetchApp.fetch(url, options);
  response = JSON.parse(response);
  
  insertProducts(response._embedded.content);
}

function insertProducts(products) {  
  var data = [];
  
  products.map(function (product) {
    data.push([product.name, product.properties.description]);
  });
  
  var range = SpreadsheetApp.getActiveSpreadsheet().getRange("A2:B" + (data.length + 1));
  range.setValues(data); 
}

function onOpen() {
  var ui = SpreadsheetApp.getUi();
  
  ui.createMenu("Umbraco")
      .addItem("Get products", "getProducts")
      .addToUi();
}