diff --git a/oca_port/app.py b/oca_port/app.py
index cdb0b17..7669cb8 100644
--- a/oca_port/app.py
+++ b/oca_port/app.py
@@ -26,11 +26,11 @@ class App(Output):
             string representation of the source branch, e.g. 'origin/15.0'
         target:
             string representation of the target branch, e.g. 'origin/16.0'
+        addon:
+            the name of the module to process
         destination:
             string representation of the destination branch,
             e.g. 'camptocamp/16.0-addon-dev'
-        addon:
-            the name of the module to process
         source_version:
             Source Odoo version. To set if it cannot be detected from 'source'.
         target_version:
@@ -60,12 +60,12 @@ class App(Output):
             to not trigger the "API rate limit exceeded" error).
     """
 
-    source: object
-    target: object
-    destination: object
+    source: str
+    target: str
     addon: str
-    source_version: str
-    target_version: str
+    destination: str = None
+    source_version: str = None
+    target_version: str = None
     repo_path: str = ""
     repo_name: str = None
     upstream_org: str = "OCA"