diff --git a/litellm/completion_extras/litellm_responses_transformation/transformation.py b/litellm/completion_extras/litellm_responses_transformation/transformation.py
index cf227cfa7d1..13dd41f9b86 100644
--- a/litellm/completion_extras/litellm_responses_transformation/transformation.py
+++ b/litellm/completion_extras/litellm_responses_transformation/transformation.py
@@ -434,6 +434,8 @@ class LiteLLMResponsesTransformationHandler(CompletionTransformationBridge):
                         "content": self._convert_content_to_responses_format(content, cast(str, role)),
                     }
                 )
+            elif role == "assistant":
+                input_items.extend(_reasoning_input_items(msg))
 
         return input_items, instructions
 
diff --git a/litellm/llms/anthropic/experimental_pass_through/responses_adapters/transformation.py b/litellm/llms/anthropic/experimental_pass_through/responses_adapters/transformation.py
index 23a9a60d810..6d47d0de19f 100644
--- a/litellm/llms/anthropic/experimental_pass_through/responses_adapters/transformation.py
+++ b/litellm/llms/anthropic/experimental_pass_through/responses_adapters/transformation.py
@@ -110,8 +110,8 @@ class LiteLLMAnthropicToResponsesAPIAdapter:
     def _summary_part_text(part: object) -> str:
         if isinstance(part, Mapping):
             mapping: Final = cast(Mapping[str, Any], part)  # cast-ok: summary parts are untyped provider json
-            return str(mapping.get("text", ""))
-        return str(getattr(part, "text", ""))
+            return str(mapping.get("text") or "")
+        return str(getattr(part, "text", None) or "")
 
     @classmethod
     def _thinking_blocks_from_reasoning_item(