Update tools.py

tools.py

@@ -3,28 +3,17 @@
 
 # Arithmetic functions
 
-def add(*numbers: float) -> float:
-    """Add any number of numbers.
+def add(a: float, b: float) -> float:
+    """Add two numbers.
     
     Args:
-        *numbers: Variable number of numbers to add
+        a: First number
+        b: Second number
 
     Returns:
-        Sum of all input numbers
+        Result number
     """
-    return sum(numbers)
-
-#def add(a: float, b: float) -> float:
-#    """Add two numbers.
-#    
-#    Args:
-#        a: First number
-#        b: Second number
-#
-#    Returns:
-#        Result number
-#    """
-#    return a + b
+    return a + b
 
 def subtract(a: float, b: float) -> float:
     """Subtract two numbers.