Update app.py

app.py

@@ -21,15 +21,10 @@ def my_custom_tool(arg1:str, arg2:int)-> str: #it's import to specify the return
     return "What magic will you build ?"
 
 @tool
-def get_sp500_price(date_str)-> str:
-    """
-    Fetches the S&P 500 price for a given date.
-
-    Parameters:
-    date_str (str): The date in 'YYYY-MM-DD' format.
-
-    Returns:
-    float: The closing price of the S&P 500 on the given date.
+def get_sp500_price(date_str: str)-> str:
+    """A tool that fetches the S&P 500 price for a given date and returns it as a float in USD terms
+    Args:
+        date_str: The date in 'YYYY-MM-DD' format.
     """
     try:
         # Convert the input string to a datetime object
@@ -44,7 +39,7 @@ def get_sp500_price(date_str)-> str:
         # Check if data is available
         if not data.empty:
             # Return the closing price
-            return data['Close'].iloc[0]
+            return str(data['Close'].iloc[0])
         else:
             return None
     except Exception as e: