How do I get or set individual cells in a Google Spreadsheet from bash

I could really use a way to get or set individual cells in a Google Spreadsheet from bash, without having to download the entire sheet, make an update and re-upload the entire sheet. Is this the closest: https://developers.google.com/sheets/api/quickstart/apps-script where we have to create a script on the Google site and run that script? I believe there used to be wget/curl methods.