758
tar -vczfx123 ought to do it
(imgs.xkcd.com)
img title="I don't know what's worse--the fact that after 15 years of using tar I still can't keep the flags straight, or that after 15 years of technological advancement I'm still mucking with tar flags that were 15 years old when I started."
That would be
-t, which I tend to remember as "test", as in testing to see what is inside the archive!tealdeer is a great program to have installed for easily getting a breakdown of the flags of pretty much any CLI app that at least I can ever think of!