From 95a451ef2cb0967dd6003ac8e265ed59b3148406 Mon Sep 17 00:00:00 2001
From: ccurme <chester.curme@gmail.com>
Date: Mon, 6 Oct 2025 10:14:43 -0400
Subject: [PATCH] fix(openai): disable stream_usage in chat completions if
 OPENAI_BASE_URL is set (#33298)

This env var is used internally by the OpenAI client.
---
 .../langchain_openai/chat_models/base.py      | 29 ++++++++++---------
 1 file changed, 16 insertions(+), 13 deletions(-)

diff --git a/libs/partners/openai/langchain_openai/chat_models/base.py b/libs/partners/openai/langchain_openai/chat_models/base.py
index 0400c1f98bb..3fad2400b2c 100644
--- a/libs/partners/openai/langchain_openai/chat_models/base.py
+++ b/libs/partners/openai/langchain_openai/chat_models/base.py
@@ -776,20 +776,23 @@ class BaseChatOpenAI(BaseChatModel):
         self.openai_api_base = self.openai_api_base or os.getenv("OPENAI_API_BASE")
 
         # Enable stream_usage by default if using default base URL and client
-        if all(
-            getattr(self, key, None) is None
-            for key in (
-                "stream_usage",
-                "openai_proxy",
-                "openai_api_base",
-                "base_url",
-                "client",
-                "root_client",
-                "async_client",
-                "root_async_client",
-                "http_client",
-                "http_async_client",
+        if (
+            all(
+                getattr(self, key, None) is None
+                for key in (
+                    "stream_usage",
+                    "openai_proxy",
+                    "openai_api_base",
+                    "base_url",
+                    "client",
+                    "root_client",
+                    "async_client",
+                    "root_async_client",
+                    "http_client",
+                    "http_async_client",
+                )
             )
+            and "OPENAI_BASE_URL" not in os.environ
         ):
             self.stream_usage = True