diff --git a/libs/partners/chroma/tests/unit_tests/test_async_vectorstores.py b/libs/partners/chroma/tests/unit_tests/test_async_vectorstores.py
index 845026f1d05..90193b5dac0 100644
--- a/libs/partners/chroma/tests/unit_tests/test_async_vectorstores.py
+++ b/libs/partners/chroma/tests/unit_tests/test_async_vectorstores.py
@@ -82,7 +82,7 @@ class MockAsyncCollection:
 class MockAsyncClient:
     """Mock async client for testing."""
 
-    def __init__(self):
+    def __init__(self) -> None:
         self.collections: dict[str, MockAsyncCollection] = {}
 
     async def get_or_create_collection(
@@ -440,3 +440,4 @@ async def test_concurrent_async_operations() -> None:
     assert all(results[0])  # First add_texts returned IDs
     assert all(results[1])  # Second add_texts returned IDs
     assert isinstance(results[2], list)  # Search returned documents
+