diff --git a/litellm/llms/anthropic/experimental_pass_through/responses_adapters/streaming_iterator.py b/litellm/llms/anthropic/experimental_pass_through/responses_adapters/streaming_iterator.py
index 967329d9c42..0ecac7c879f 100644
--- a/litellm/llms/anthropic/experimental_pass_through/responses_adapters/streaming_iterator.py
+++ b/litellm/llms/anthropic/experimental_pass_through/responses_adapters/streaming_iterator.py
@@ -124,7 +124,9 @@ class AnthropicResponsesStreamWrapper:
         self._current_block_index += 1
         return self._current_block_index
 
-    def _make_error_chunk(self, message: str) -> dict[str, Any]:
+    def _make_error_chunk(
+        self, message: str
+    ) -> dict[str, Any]:  # mutable-ok: queued into _chunk_queue and returned from __anext__, both typed dict[str, Any]
         return {
             "type": "error",
             "error": {"type": "api_error", "message": message},