diff --git a/music_kraken/download/__init__.py b/music_kraken/download/__init__.py
index 6ec70dd..0eadffc 100644
--- a/music_kraken/download/__init__.py
+++ b/music_kraken/download/__init__.py
@@ -164,18 +164,36 @@ class Downloader:
         for page in self.get_pages():
             yield page, limit_generator(page.search(query=query), limit=results_per_page)
 
-    def fetch_details(self, data_object: DataObject, stop_at_level: int = 1, **kwargs) -> DataObject:
+    def fetch_details(self, data_object: DataObject, **kwargs) -> DataObject:
+        """Fetches more details for the given data object.
+        This uses every source contained in data_object.source_collection that has a page.
+
+        Args:
+            data_object (DataObject): The data object to fetch details for.
+
+        Returns:
+            DataObject: The same data object, but with more details.
+        """
+
         source: Source
         for source in data_object.source_collection.get_sources(source_type_sorting={
             "only_with_page": True,
         }):
-            new_data_object = self.fetch_from_source(source=source, stop_at_level=stop_at_level)
+            new_data_object = self.fetch_from_source(source=source, **kwargs)
             if new_data_object is not None:
                 data_object.merge(new_data_object)
 
         return data_object
 
     def fetch_from_source(self, source: Source, **kwargs) -> Optional[DataObject]:
+        """Gets a data object from the given source.
+
+        Args:
+            source (Source): The source to get the data object from.
+
+        Returns:
+            Optional[DataObject]: If a data object can be retrieved, it is returned. Otherwise, None is returned.
+        """
         if not source.has_page:
             return None
         
@@ -192,6 +210,15 @@ class Downloader:
         return data_object
 
     def fetch_from_url(self, url: str) -> Optional[DataObject]:
+        """This function tries to detect the source of the given url and fetches the data object from it.
+
+        Args:
+            url (str): The url to fetch the data object from.
+
+        Returns:
+            Optional[DataObject]: The fetched data object, or None if no source could be detected or if no object could be retrieved.
+        """
+
         source = Source.match_url(url, ALL_SOURCE_TYPES.MANUAL)
         if source is None:
             return None