Library /sys$common/syshlp/lse$menu.hlb HELP_KEY  *Conan The Librarian (sorry for the slow response - running on an old VAX)

  Syntax:  HELP KEY user_key_name

  Displays help information for the indicated key.

  The help text describes the functionality bound to that key.  If you
  enter HELP KEY CTRL/E, for example, you get the help text for the
  EXPAND command.