diff --git a/art.py b/art.py
index 5570decd9..2884b950b 100644
--- a/art.py
+++ b/art.py
@@ -67,7 +67,7 @@ def get_art_site_url(actor_json: {}) -> str:
             get_attachment_property_value(property_value)
         if not prop_value_name:
             continue
-        art_text = remove_html(property_value[prop_value_name])
+        art_text: str = remove_html(property_value[prop_value_name])
         if not string_contains(art_text, art_sites):
             continue
         if not resembles_url(art_text):
@@ -87,16 +87,18 @@ def set_art_site_url(actor_json: {}, art_site_url: str) -> None:
         actor_json['attachment']: list[dict] = []
 
     # remove any existing value
-    property_found = None
+    property_found: dict = None
     for property_value in actor_json['attachment']:
         if not isinstance(property_value, dict):
             print("WARN: actor attachment is not dict: " + str(property_value))
             continue
-        name_value = None
+        name_value: str = None
         if property_value.get('name'):
-            name_value = property_value['name'].lower()
+            if isinstance(property_value['name'], str):
+                name_value = property_value['name'].lower()
         elif property_value.get('schema:name'):
-            name_value = property_value['schema:name'].lower()
+            if isinstance(property_value['schema:name'], str):
+                name_value = property_value['schema:name'].lower()
         if not name_value:
             continue
         if not property_value.get('type'):
@@ -113,11 +115,13 @@ def set_art_site_url(actor_json: {}, art_site_url: str) -> None:
         if not isinstance(property_value, dict):
             print("WARN: actor attachment is not dict: " + str(property_value))
             continue
-        name_value = None
+        name_value: str = None
         if property_value.get('name'):
-            name_value = property_value['name']
+            if isinstance(property_value['name'], str):
+                name_value = property_value['name']
         elif property_value.get('schema:name'):
-            name_value = property_value['schema:name']
+            if isinstance(property_value['schema:name'], str):
+                name_value = property_value['schema:name']
         if not name_value:
             continue
         if not property_value.get('type'):