Update app.py

app.py

@@ -9,14 +9,26 @@ from Gradio_UI import GradioUI
 
 # Below is an example of a tool that does nothing. Amaze us with your creativity !
 @tool
-def my_custom_tool(arg1:str, arg2:int)-> str: #it's import to specify the return type
-    #Keep this format for the description / args / args description but feel free to modify the tool
-    """A tool that does nothing yet 
+def calculate_yen_by_usd(usd: str, exchange_rate: int) -> str: #it's import to specify the return type    
+    """Calculates the equivalent amount in Japanese Yen given USD and the exchange rate.
     Args:
-        arg1: the first argument
-        arg2: the second argument
+        usd: The amount of USD to convert (as a string).
+        exchange_rate: The exchange rate (JPY per USD).
+    Returns:
+        A string representing the total Yen after exchange, or an error message if input is invalid.
     """
-    return "What magic will you build ?"
+    try:
+        usd_amount = float(usd)  # Convert USD input to a float
+        if usd_amount < 0:
+            return "USD amount must be non-negative."
+
+        if exchange_rate <= 0:  # Check for invalid exchange rate
+            return "Exchange rate must be positive."
+
+        yen_amount = usd_amount * exchange_rate
+        return str(int(yen_amount))  # Return the Yen amount as a string (integer part)
+    except ValueError:
+        return "Invalid USD amount. Please enter a numerical value."
 
 @tool
 def get_current_time_in_timezone(timezone: str) -> str: