diff --git a/swarms/swarms.py b/swarms/swarms.py
index c2c7f8b8..c47cf93d 100644
--- a/swarms/swarms.py
+++ b/swarms/swarms.py
@@ -59,7 +59,7 @@ class HierarchicalSwarm:
 
 
 
-    def initialize_llm(self, llm_class):
+    def initialize_llm(self, llm_class: str = None):
         """
         Init LLM