Update tools.py

tools.py

@@ -1,6 +1,8 @@
 # Automatic function calling
 # https://ai.google.dev/gemini-api/docs/function-calling
 
+# Arithmetic functions
+
 def add(a: float, b: float) -> float:
     """Add two numbers.
     
@@ -60,4 +62,6 @@ def modulus(a: float, b: float) -> float:
     Returns:
         Result number
     """
-    return a % b
+    return a % b
+
+# TODO: Other functions