diff --git a/src/codeinterpreterapi/callbacks/markdown/callbacks.py b/src/codeinterpreterapi/callbacks/markdown/callbacks.py
index f9277df..e629fb3 100644
--- a/src/codeinterpreterapi/callbacks/markdown/callbacks.py
+++ b/src/codeinterpreterapi/callbacks/markdown/callbacks.py
@@ -32,10 +32,11 @@ def on_llm_end(self, response: LLMResult, **kwargs: Any) -> None:
 
     def on_chain_start(self, serialized: Dict[str, Any], inputs: Dict[str, Any], **kwargs: Any) -> None:
         self.step_count += 1
-        chain_name = serialized.get("name", "Unknown Chain")
-        self._write_header(f"Chain Start - {chain_name}")
-        self._write_serialized(serialized)
-        self._write_inputs(inputs)
+        if serialized:
+            chain_name = serialized.get("name", "Unknown Chain")
+            self._write_header(f"Chain Start - {chain_name}")
+            self._write_serialized(serialized)
+            self._write_inputs(inputs)
 
     def on_chain_end(self, outputs: Dict[str, Any], **kwargs: Any) -> None:
         self._write_header("Chain End")