Update tool.py

tool.py

@@ -41,11 +41,11 @@ class SimpleTool(Tool):
         }
 
         # Convert `value` to float if it's a string
-            if isinstance(value, str):
-                try:
-                    value = float(value)
-                except ValueError:
-                    raise ValueError("Value must be a number")
+        if isinstance(value, str):
+            try:
+                value = float(value)
+            except ValueError:
+                raise ValueError("Value must be a number")
         
         # Check if the units are valid
         if from_unit not in conversion_rates or to_unit not in conversion_rates[from_unit]: