Update app.py

app.py

@@ -10,17 +10,20 @@ from Gradio_UI import GradioUI
 
 # Below is an example of a tool that does nothing. Amaze us with your creativity !
 @tool
-def compute_derivative(expr_str:str, var_str: str = 'x')-> 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 computes the symbolic derivative of an expression
+def compute_derivative(expr_str: str, var_str: str = 'x') -> str:
+    """
+    A tool that computes the symbolic derivative of an expression.
+
     Args:
-        - expr_str: str - A string representing the expression (e.g., "x**2 + sin(x)")
-        - var_str: str - The variable with respect to which to differentiate (default "x")
+        expr_str (str): A string representing the expression (e.g., "x**2 + sin(x)").
+        var_str (str): The variable with respect to which to differentiate (default: "x").
+
     """
     var = symbols(var_str)
     expr = sympify(expr_str)
     derivative = diff(expr, var)
-    return derivative
+    return str(derivative)
+
 
 @tool
 def get_current_time_in_timezone(timezone: str) -> str: