One thing about Kermit- it used to be the gold standard for CLI usability: editing, history, ESC-completion and context sensitive ?-help. I think it was directly inspired by the TOPS-20 operating system.

For example, user types "?" after entering screen

    C-Kermit>screen ? screen action, one of the following:
     clear    cleol    move-to
    C-Kermit>screen _