Check out NeWS, circa 1990. Or Arthur Van Hoffs HyperNeWs around the same time.

Edit: or Apples MPW shell back in the late 80s had a posixy set of command line tools that came with a shell called "commando". When invoked, it presented a dialog of all the tools options and constructed the command line from your choices. Kind if like training wheels, and it was smart enough to disable conflicting options, or to prompt for paths as appropriate. It showed the command syntax being built up. Eventually, I think it made its way to a/ux in 1992 or so.