fix(lint): update return/yield types to ModelResponseStream

- langgraph sse_iterator: update return types from ModelResponse to
  ModelResponseStream across all methods
- bedrock agentcore: fix async generator yield type annotation
- vertex gemini: add type: ignore for MyPy narrowing false positive

litellm/llms/bedrock/chat/agentcore/transformation.py

@@ -601,7 +601,7 @@ class AmazonAgentCoreConfig(BaseConfig, BaseAWSLLM):
         self,
         response: httpx.Response,
         model: str,
-    ) -> AsyncGenerator[ModelResponse, None]:
+    ) -> AsyncGenerator[ModelResponseStream, None]:
         """
         Internal async generator that parses SSE and yields ModelResponse chunks.
         """

litellm/llms/langgraph/chat/sse_iterator.py

@@ -11,7 +11,7 @@ from typing import TYPE_CHECKING, Optional
 import httpx
 
 from litellm._logging import verbose_logger
-from litellm.types.utils import Delta, ModelResponse, ModelResponseStream, StreamingChoices
+from litellm.types.utils import Delta, ModelResponseStream, StreamingChoices
 
 if TYPE_CHECKING:
     pass
@@ -44,7 +44,7 @@ class LangGraphSSEStreamIterator:
         self.async_line_iterator = self.response.aiter_lines()
         return self
 
-    def _parse_sse_line(self, line: str) -> Optional[ModelResponse]:
+    def _parse_sse_line(self, line: str) -> Optional[ModelResponseStream]:
         """
         Parse a single SSE line and return a ModelResponse chunk if applicable.
 
@@ -71,7 +71,7 @@ class LangGraphSSEStreamIterator:
 
         return None
 
-    def _process_data(self, data) -> Optional[ModelResponse]:
+    def _process_data(self, data) -> Optional[ModelResponseStream]:
         """
         Process parsed data from SSE stream.
 
@@ -101,7 +101,7 @@ class LangGraphSSEStreamIterator:
 
         return None
 
-    def _process_messages_event(self, payload) -> Optional[ModelResponse]:
+    def _process_messages_event(self, payload) -> Optional[ModelResponseStream]:
         """
         Process a messages event from the stream.
 
@@ -128,7 +128,7 @@ class LangGraphSSEStreamIterator:
 
         return None
 
-    def _process_metadata_event(self, payload) -> Optional[ModelResponse]:
+    def _process_metadata_event(self, payload) -> Optional[ModelResponseStream]:
         """
         Process a metadata event, which may signal the end of the stream.
         """
@@ -177,7 +177,7 @@ class LangGraphSSEStreamIterator:
 
         return chunk
 
-    def __next__(self) -> ModelResponse:
+    def __next__(self) -> ModelResponseStream:
         """Sync iteration - parse SSE events and yield ModelResponse chunks."""
         try:
             if self.line_iterator is None:
@@ -205,7 +205,7 @@ class LangGraphSSEStreamIterator:
             verbose_logger.error(f"Error in LangGraph SSE stream: {str(e)}")
             raise StopIteration
 
-    async def __anext__(self) -> ModelResponse:
+    async def __anext__(self) -> ModelResponseStream:
         """Async iteration - parse SSE events and yield ModelResponse chunks."""
         try:
             if self.async_line_iterator is None:

litellm/llms/vertex_ai/gemini/vertex_and_google_ai_studio_gemini.py

@@ -2093,7 +2093,7 @@ class VertexGeminiConfig(VertexAIBaseConfig, BaseConfig):
                     chat_completion_logprobs=chat_completion_logprobs,
                     image_response=image_response,
                 )
-                model_response.choices.append(choice)
+                model_response.choices.append(choice)  # type: ignore[arg-type]
             elif isinstance(model_response, ModelResponse):
                 choice = litellm.Choices(
                     finish_reason=VertexGeminiConfig._check_finish_reason(