diff --git a/tiramisu_cmdline_parser.py b/tiramisu_cmdline_parser.py
index c2dbe17..1730be1 100644
--- a/tiramisu_cmdline_parser.py
+++ b/tiramisu_cmdline_parser.py
@@ -219,7 +219,10 @@ class TiramisuCmdlineParser(ArgumentParser):
             group.add_argument(*args, **kwargs)
 
 
-    def parse_args(self, *args, **kwargs):
+    def parse_args(self,
+                   *args,
+                   valid_mandatory=True,
+                   **kwargs):
         kwargs['namespace'] = TiramisuNamespace(self.config)
         try:
             namespaces = super().parse_args(*args, **kwargs)
@@ -236,13 +239,14 @@ class TiramisuCmdlineParser(ArgumentParser):
                 self.error('the following arguments are required: {}'.format(name))
             else:
                 self.error('unrecognized arguments: {}'.format(name))
-        for key in self.config.value.mandatory():
-            if self.fullpath or '.' not in key:
-                name = key
-            else:
-                name = key.rsplit('.', 1)[1]
-            args = self._gen_argument(name, self.config.option(key).property.get())
-            self.error('the following arguments are required: {}'.format(args))
+        if valid_mandatory:
+            for key in self.config.value.mandatory():
+                if self.fullpath or '.' not in key:
+                    name = key
+                else:
+                    name = key.rsplit('.', 1)[1]
+                args = self._gen_argument(name, self.config.option(key).property.get())
+                self.error('the following arguments are required: {}'.format(args))
         return namespaces
 
     def format_usage(self,