diff --git a/ce/interp.c b/ce/interp.c
index 27121e8..00e1d7a 100644
--- a/ce/interp.c
+++ b/ce/interp.c
@@ -334,6 +334,7 @@ static void help (struct context* context) {
   cprintf (context, "terminfo\n");
   cprintf (context, "cls\n");
   cprintf (context, "mkvol        <volume> <filesystem> <device>\n");
+  cprintf (context, "format       <device> <filesystem>\n");
   cprintf (context, "quit\n");
 }