diff --git a/eqa_insert.py b/eqa_insert.py
index 35d54c4..db94d1e 100644
--- a/eqa_insert.py
+++ b/eqa_insert.py
@@ -25,7 +25,7 @@ class EnhancedQAInsertConfig(BaseModel):
     """
     # config for text_splitter
     type: Optional[str] = 'RecursiveCharacter'
-    chunk_size: int = 300
+    chunk_size: Optional[int] = 300
     splitter_kwargs: Optional[Dict[str, Any]] = {}
     # config for sentence_embedding
     model: Optional[str] = 'all-MiniLM-L6-v2'