[TeMPOraL]

Back when I last did it with GPT-4-Turbo, asking for an ICS file would get it to refuse on the grounds that it cannot make a file. Asking for encoding in iCal fomat, however, would make it output into a Markdown code block, which I'd then copy-paste into Notepad and save as ICS.

These days, you may also try asking it to "use Python" for the purpose, in which case it will make you the file (by writing code that writes the file and executing it), but it's likely to make more mistakes because it has to encode the result into a Python string or array.