diff --git a/core/database/utils.py b/core/database/utils.py
index e44317e..65f5151 100644
--- a/core/database/utils.py
+++ b/core/database/utils.py
@@ -37,6 +37,7 @@ def list_names(
     query = {}
     if has_annotation:
         query['annotation'] = {'$ne': None}
+    # execute query
     res_list = collection.find(
         filter=query,
         projection={
@@ -44,7 +45,9 @@ def list_names(
             'name': True,
         },
     )
-    return list(res_list)
+    # extract information
+    name_list = [elem['name'] for elem in res_list]
+    return name_list
 
 
 def total_documents(