diff --git a/kiss b/kiss
index b1e7b51..2619bfc 100755
--- a/kiss
+++ b/kiss
@@ -1498,19 +1498,19 @@ args() {
     # not be used here as they would conflict with kiss extensions.
     case $action in
         a|alternatives)
-            case $1 in */*|*\**|*\!*|*\[*|*\]*)
-                die "Invalid argument: '/!*[]' ($1)"
+            case $1 in *\**|*\!*|*\[*|*\]*|*' '*|*/*)
+                die "Invalid argument: '!*[] /' ($1)"
             esac
         ;;
 
         b|build|c|checksum|d|download|i|install|l|list|r|remove)
             case ${action%%"${action#?}"}-$* in
-                i-*[\*\!\[\]]*)
-                    die "Arguments contain invalid characters: '!*[]' ($*)"
+                i-*\!*|i-*\**|i-*\[*|i-*\]*|i-*' '*)
+                    die "Arguments contain invalid characters: '!*[] ' ($*)"
                 ;;
 
-                [!i]-*[\*\!\[\]/]*)
-                    die "Arguments contain invalid characters: '!*[]/' ($*)"
+                [!i]-*\!*|[!i]-*\**|[!i]-*\[*|[!i]-*\]*|[!i]-*' '*|[!i]-*/*)
+                    die "Arguments contain invalid characters: '!*[] /' ($*)"
                 ;;
 
                 [!l]-)