chore: Filter event with only functions, thought_signatures when adding to memory

PiperOrigin-RevId: 786825628

Author: DeanChensj

src/google/adk/memory/vertex_ai_memory_bank_service.py

@@ -66,7 +66,9 @@ async def add_session_to_memory(self, session: Session):
 
     events = []
     for event in session.events:
-      if event.content and event.content.parts:
+      if _should_filter_out_event(event.content):
+        continue
+      if event.content:
         events.append({
             'content': event.content.model_dump(exclude_none=True, mode='json')
         })
@@ -150,3 +152,13 @@ def _convert_api_response(api_response) -> Dict[str, Any]:
   if hasattr(api_response, 'body'):
     return json.loads(api_response.body)
   return api_response
+
+
+def _should_filter_out_event(content: types.Content) -> bool:
+  """Returns whether the event should be filtered out."""
+  if not content or not content.parts:
+    return True
+  for part in content.parts:
+    if part.text or part.inline_data or part.file_data:
+      return False
+  return True

tests/unittests/memory/test_vertex_ai_memory_bank_service.py

@@ -45,6 +45,20 @@
             author='user',
             timestamp=12345,
         ),
+        # Function call event, should be ignored
+        Event(
+            id='666',
+            invocation_id='456',
+            author='agent',
+            timestamp=23456,
+            content=types.Content(
+                parts=[
+                    types.Part(
+                        function_call=types.FunctionCall(name='test_function')
+                    )
+                ]
+            ),
+        ),
     ],
 )