diff --git a/api/s23_options.py b/api/s23_options.py
index cb1fc5a..1a02b6b 100644
--- a/api/s23_options.py
+++ b/api/s23_options.py
@@ -22,9 +22,10 @@ def inp_in_option(section: list[str]) -> ChangeSet:
 
         tokens = s.strip().split()
         if tokens[0].upper() == 'PATTERN': # can not upper id
-            cs |= { 'PATTERN' : tokens[1] }
+            value = tokens[1] if len(tokens) > 1 else ''
+            cs |= { 'PATTERN' : value }
         elif tokens[0].upper() == 'QUALITY': # can not upper trace node
-            value = tokens[1]
+            value = tokens[1] if len(tokens) > 1 else ''
             if len(tokens) > 2:
                 value += f' {tokens[2]}'
             cs |= { 'QUALITY' : value }