diff --git a/servers/fastapi/services/llm_client.py b/servers/fastapi/services/llm_client.py
index 6fb8ec4e..72205c93 100644
--- a/servers/fastapi/services/llm_client.py
+++ b/servers/fastapi/services/llm_client.py
@@ -886,7 +886,7 @@ class LLMClient:
                     current_id = tool_id or current_id
                     if current_arguments is None:
                         current_arguments = tool_arguments
-                    else:
+                    elif tool_arguments:
                         current_arguments += tool_arguments
 
         if current_id is not None:
@@ -1233,7 +1233,7 @@ class LLMClient:
                     current_id = tool_id or current_id
                     if current_arguments is None:
                         current_arguments = tool_arguments
-                    else:
+                    elif tool_arguments:
                         current_arguments += tool_arguments
 
                 if current_name == "ResponseSchema":