Add docstring to todays_date functions!

app.py

@@ -22,6 +22,11 @@ def my_custom_tool(arg1:str, arg2:int)-> str: #it's import to specify the return
 
 @tool
 def todays_date():
+    """ Returns the current date in the format of 'Month Day, Year' 
+    
+    Returns:
+        str: The current date in the format of 'Month Day
+    """
     today = date.today()
     return today.strftime("%b %d, %Y")