From eb6164ca7de53a2d7170ae7473a72fe2c07ad80d Mon Sep 17 00:00:00 2001
From: Natalie Kong <186588905+Nataliekooong@users.noreply.github.com>
Date: Fri, 25 Sep 2026 17:56:28 -0400
Subject: [PATCH 1/2] fix(streaming): skip pydantic model_* attributes before
 getattr in stream emptiness check

---
 .../model_response_utils.py                   |  9 +++--
 .../test_model_response_utils.py              | 35 +++++++++++++++++++
 2 files changed, 42 insertions(+), 2 deletions(-)

diff --git a/litellm/litellm_core_utils/model_response_utils.py b/litellm/litellm_core_utils/model_response_utils.py
index dc4f375daa7..a378c160077 100644
--- a/litellm/litellm_core_utils/model_response_utils.py
+++ b/litellm/litellm_core_utils/model_response_utils.py
@@ -158,8 +158,8 @@ def _is_choice_non_empty(choice: StreamingChoices) -> bool:
         # Skip private attributes, methods, and known empty fields
         if (
             attr_name.startswith("_")
-            or callable(_attribute_of(choice, attr_name))
             or attr_name.startswith("model_")
+            or callable(_attribute_of(choice, attr_name))
             or attr_name
             in {
                 "finish_reason",
@@ -197,7 +197,12 @@ def _is_delta_non_empty(delta: Delta) -> bool:
     # Check all regular attributes of the delta object
     for attr_name in dir(delta):
         # Skip private attributes, methods, and Pydantic-specific fields
-        if attr_name.startswith("_") or callable(_attribute_of(delta, attr_name)) or attr_name.startswith("model_"):
+        if (
+            attr_name.startswith("_")
+            or attr_name.startswith("model_")
+            or callable(_attribute_of(delta, attr_name))
+            or attr_name.startswith("model_")
+        ):
             continue
 
         delta_attr_value: object = getattr(delta, attr_name, None)
diff --git a/tests/test_litellm/litellm_core_utils/test_model_response_utils.py b/tests/test_litellm/litellm_core_utils/test_model_response_utils.py
index 2ffe5853c4d..aff7c81ee07 100644
--- a/tests/test_litellm/litellm_core_utils/test_model_response_utils.py
+++ b/tests/test_litellm/litellm_core_utils/test_model_response_utils.py
@@ -1,3 +1,4 @@
+import warnings
 from litellm.litellm_core_utils.model_response_utils import (
     is_model_response_stream_empty,
 )
@@ -58,3 +59,37 @@ def test_is_model_response_stream_empty_with_custom_value():
 
     setattr(chunk.choices[0].delta, "custom_field", "test")
     assert is_model_response_stream_empty(chunk) is False
+
+
+
+def test_is_model_response_stream_empty_does_not_access_deprecated_pydantic_instance_attributes():
+    chunk = ModelResponseStream(
+        id="chatcmpl-C3sWKN2RWbn6CZ1IGU2QCpRh4RhYf",
+        created=1755040596,
+        model="gpt-4o-mini",
+        object="chat.completion.chunk",
+        system_fingerprint="fp_34a54ae93c",
+        choices=[
+            StreamingChoices(
+                finish_reason=None,
+                index=0,
+                delta=Delta(
+                    provider_specific_fields=None,
+                    content=None,
+                    role=None,
+                    function_call=None,
+                    tool_calls=None,
+                    audio=None,
+                ),
+                logprobs=None,
+            )
+        ],
+        provider_specific_fields=None,
+    )
+
+    with warnings.catch_warnings():
+        warnings.filterwarnings(
+            "error",
+            message=r".*'model_(computed_)?fields' attribute on the instance is deprecated",
+        )
+        assert is_model_response_stream_empty(chunk) is True

From 337e27f39bd17206602245ede91493be7f1542e7 Mon Sep 17 00:00:00 2001
From: Natalie Kong <186588905+Nataliekooong@users.noreply.github.com>
Date: Sat, 26 Sep 2026 00:35:47 -0400
Subject: [PATCH 2/2] fix(streaming): drop redundant model_ prefix check in
 delta loop

---
 litellm/litellm_core_utils/model_response_utils.py | 7 +------
 1 file changed, 1 insertion(+), 6 deletions(-)

diff --git a/litellm/litellm_core_utils/model_response_utils.py b/litellm/litellm_core_utils/model_response_utils.py
index a378c160077..77d85c52404 100644
--- a/litellm/litellm_core_utils/model_response_utils.py
+++ b/litellm/litellm_core_utils/model_response_utils.py
@@ -197,12 +197,7 @@ def _is_delta_non_empty(delta: Delta) -> bool:
     # Check all regular attributes of the delta object
     for attr_name in dir(delta):
         # Skip private attributes, methods, and Pydantic-specific fields
-        if (
-            attr_name.startswith("_")
-            or attr_name.startswith("model_")
-            or callable(_attribute_of(delta, attr_name))
-            or attr_name.startswith("model_")
-        ):
+        if attr_name.startswith("_") or attr_name.startswith("model_") or callable(_attribute_of(delta, attr_name)):
             continue
 
         delta_attr_value: object = getattr(delta, attr_name, None)