diff --git a/google/genai/_interactions/types/user_input_step.py b/google/genai/_interactions/types/user_input_step.py
index 292b079dc..25e0e5669 100644
--- a/google/genai/_interactions/types/user_input_step.py
+++ b/google/genai/_interactions/types/user_input_step.py
@@ -15,7 +15,7 @@
 
 # File generated from our OpenAPI spec by Stainless. See CONTRIBUTING.md for details.
 
-from typing import List, Optional
+from typing import List, Union
 from typing_extensions import Literal
 
 from .content import Content
@@ -29,4 +29,4 @@ class UserInputStep(BaseModel):
 
     type: Literal["user_input"]
 
-    content: Optional[List[Content]] = None
+    content: Union[List[Content], str, None] = None
diff --git a/google/genai/_interactions/types/user_input_step_param.py b/google/genai/_interactions/types/user_input_step_param.py
index 46a54c062..f1557ec62 100644
--- a/google/genai/_interactions/types/user_input_step_param.py
+++ b/google/genai/_interactions/types/user_input_step_param.py
@@ -17,7 +17,7 @@
 
 from __future__ import annotations
 
-from typing import Iterable
+from typing import Union, Iterable
 from typing_extensions import Literal, Required, TypedDict
 
 from .content_param import ContentParam
@@ -30,4 +30,4 @@ class UserInputStepParam(TypedDict, total=False):
 
     type: Required[Literal["user_input"]]
 
-    content: Iterable[ContentParam]
+    content: Union[Iterable[ContentParam], str]