I think IF games are solidly "command line games" - it is a game that you interact with entirely through commands you type at a... line...

Games you play at "the command line" - or, as the article puts it, "expansive and impressive games that you can run entirely in your Linux shell," is an interesting notion. I'm generally a big fan of decomposing actions out of applications into individual commands run at the shell; I had not applied the same to games.

You could run the game itself in a long running process, talking through (unix?) sockets that the individual commands know how to find. Polling in PROMPT_COMMAND could make it sufficiently interactive for some measure of real-time.

I would have to begrudgingly agree that cli games would include all infocom games would be command lines games since it doesn't have to be constrained to the command line shell like /bin/sh

I forgot to mention after my comment "play by email" games which would broaden the scope to network games since the interface could be through a shell when using sendmail.

https://en.wikipedia.org/wiki/Category:Play-by-email_video_g...

Play By Email seems marginal. It's certainly true that you can do it from the command line (I'd heartily recommend nmh over using sendmail directly), but it's sort of incidental rather than by design. That said, I'd count it.

Email to me is a type of network transfer, slower than RESTful, but reliable nonetheless.

I agree. What I think makes PBEM marginal as an example of "command-line-only" is that it is designed with email in mind as the interface, and it is only because we have command line access to email that we have command line access to the game. As I noted, though, I still think it counts.