diff --git a/src/risotto/dispatcher.py b/src/risotto/dispatcher.py
index 92c400b..d2f0d0d 100644
--- a/src/risotto/dispatcher.py
+++ b/src/risotto/dispatcher.py
@@ -239,6 +239,10 @@ class Dispatcher(register.RegisterDispatcher,
                     if get_config()['global']['debug']:
                         print_exc()
                     raise ValueError(_(f'unknown parameter in "{uri}": "{key}"'))
+                except ValueError as err:
+                    if get_config()['global']['debug']:
+                        print_exc()
+                    raise ValueError(_(f'invalid value for "{key}" in "{uri}": {err}'))
             # check mandatories options
             if check_role and get_config().get('global').get('check_role'):
                 await self.check_role(subconfig,