xlwings Lite turns Excel into a live Python app. No Python install on the user's machine. Just a browser-based add-in with code editor, console, and deep Excel integration. It launched earlier this year and I've been using it ever since. When you use AI coders like Claude, Cursor, or Gemini to write xlwings Lite code, they don't know its constraints. They generate desktop xlwings syntax that looks right but fails silently. So I started maintaining an instruction file - a docu
