diff --git a/scilog/snippet.py b/scilog/snippet.py
index 8aa4df2..906b4b6 100644
--- a/scilog/snippet.py
+++ b/scilog/snippet.py
@@ -8,7 +8,7 @@ def typechecked(func):
     def typechecked_call(obj, *args, **kwargs):
         type_hints = get_type_hints(func)
         del type_hints["return"]
-        for arg, dtype in zip(args, type_hints):
+        for arg, dtype in zip(args, type_hints.values()):
             arg_type = type(arg)
             if dtype != arg_type:
                 raise TypeError(f"{func} expected to receive input of type {dtype.__name__} but received {arg_type.__name__}")