diff --git a/src/anthropic/_models.py b/src/anthropic/_models.py
index dc00516bc..b9b80256d 100644
--- a/src/anthropic/_models.py
+++ b/src/anthropic/_models.py
@@ -647,7 +647,7 @@ def construct_type(*, value: object, type_: object, metadata: Optional[List[Any]
         if not is_mapping(value):
             return value
 
-        _, items_type = get_args(type_)  # Dict[_, items_type]
+        items_type = args[1] if len(args) >= 2 else object  # Dict[_, items_type]
         return {key: construct_type(value=item, type_=items_type) for key, item in value.items()}
 
     if (
@@ -668,7 +668,7 @@ def construct_type(*, value: object, type_: object, metadata: Optional[List[Any]
         if not is_list(value):
             return value
 
-        inner_type = args[0]  # List[inner_type]
+        inner_type = args[0] if args else object  # List[inner_type]
         return [construct_type(value=entry, type_=inner_type) for entry in value]
 
     if origin == float:
diff --git a/src/anthropic/_utils/_transform.py b/src/anthropic/_utils/_transform.py
index 1e7e5ac80..75b09393f 100644
--- a/src/anthropic/_utils/_transform.py
+++ b/src/anthropic/_utils/_transform.py
@@ -180,7 +180,8 @@ def _transform_recursive(
         return _transform_typeddict(data, stripped_type)
 
     if origin == dict and is_mapping(data):
-        items_type = get_args(stripped_type)[1]
+        args = get_args(stripped_type)
+        items_type = args[1] if len(args) >= 2 else object
         return {key: _transform_recursive(value, annotation=items_type) for key, value in data.items()}
 
     if (
@@ -346,8 +347,9 @@ async def _async_transform_recursive(
         return await _async_transform_typeddict(data, stripped_type)
 
     if origin == dict and is_mapping(data):
-        items_type = get_args(stripped_type)[1]
-        return {key: _transform_recursive(value, annotation=items_type) for key, value in data.items()}
+        args = get_args(stripped_type)
+        items_type = args[1] if len(args) >= 2 else object
+        return {key: await _async_transform_recursive(value, annotation=items_type) for key, value in data.items()}
 
     if (
         # List[T]