diff --git a/tiramisu_json_api/api.py b/tiramisu_json_api/api.py
index 0cc4876..0d9c1e0 100644
--- a/tiramisu_json_api/api.py
+++ b/tiramisu_json_api/api.py
@@ -113,7 +113,7 @@ class TiramisuOptionOption:
 class TiramisuOptionProperty:
     # config.option(path).property
     def __init__(self,
-                 config,
+                 config: 'Config',
                  path: str,
                  model: Dict) -> None:
         self.config = config
@@ -328,8 +328,8 @@ class TiramisuOptionDescription(_Option):
                                         self.model,
                                         self.form)
         if subfunc == 'property':
-            return TiramisuOptionProperty(self.path,
-                                          self.config,
+            return TiramisuOptionProperty(self.config,
+                                          self.path,
                                           self.model.get(self.path, {}))
         if subfunc == 'value':
             return TiramisuOptionValue(self.config,
@@ -398,8 +398,8 @@ class TiramisuOption:
         if subfunc == 'property':
             if self.index != None:
                 raise NotImplementedError()
-            return TiramisuOptionProperty(self.path,
-                                          self.config,
+            return TiramisuOptionProperty(self.config,
+                                          self.path,
                                           self.model.get(self.path, {}))
         raise APIError(_('please specify a valid sub function ({})').format(subfunc))