enhance hbty func

app.py

@@ -118,6 +118,7 @@ def my_custom_tool(arg1: str, arg2: int) -> str:
 def hbty(b_day: str) -> str: #hbty = Happy Birthday to you
     """
     A tool for wishing Happy Birthday, If use query or inputs have or contain keyword "birthday" or "bday".
+    A tool that generates a happy birthday greeting whenever the user mentions 'birthday', 'bday', or asks about birthdays.
     Args:
         b_day: A string containing a question or statement to check for birthday keywords like 'birthday' or 'bday'.
     """