diff --git a/src/agents/extensions/models/litellm_model.py b/src/agents/extensions/models/litellm_model.py
index fca172fff..82779b635 100644
--- a/src/agents/extensions/models/litellm_model.py
+++ b/src/agents/extensions/models/litellm_model.py
@@ -3,6 +3,7 @@
 import json
 import time
 from collections.abc import AsyncIterator
+from copy import copy
 from typing import Any, Literal, cast, overload
 
 from openai.types.responses.response_usage import InputTokensDetails, OutputTokensDetails
@@ -300,9 +301,9 @@ async def _fetch_response(
 
         extra_kwargs = {}
         if model_settings.extra_query:
-            extra_kwargs["extra_query"] = model_settings.extra_query
+            extra_kwargs["extra_query"] = copy(model_settings.extra_query)
         if model_settings.metadata:
-            extra_kwargs["metadata"] = model_settings.metadata
+            extra_kwargs["metadata"] = copy(model_settings.metadata)
         if model_settings.extra_body and isinstance(model_settings.extra_body, dict):
             extra_kwargs.update(model_settings.extra_body)