diff --git a/llama_stack/models/llama/llama4/chat_format.py b/llama_stack/models/llama/llama4/chat_format.py
index 1debadcc5..1574eeb5e 100644
--- a/llama_stack/models/llama/llama4/chat_format.py
+++ b/llama_stack/models/llama/llama4/chat_format.py
@@ -303,6 +303,7 @@ class ChatFormat:
                     arguments_json=json.dumps(tool_arguments),
                 )
             )
+            content = ""
 
         return RawMessage(
             role="assistant",