fix: include auth headers in responses websocket handshake

src/agents/models/openai_responses.py

@@ -1377,10 +1377,15 @@ async def _prepare_websocket_request(
 
     def _merge_websocket_headers(self, extra_headers: Mapping[str, Any]) -> dict[str, str]:
         headers: dict[str, str] = {}
-        for key, value in self._client.default_headers.items():
-            if _is_openai_omitted_value(value):
-                continue
-            headers[key] = str(value)
+        auth_headers = getattr(self._client, "auth_headers", {})
+        for source in (auth_headers, self._client.default_headers):
+            for key, value in source.items():
+                header_key = str(key)
+                for existing_key in list(headers):
+                    if existing_key.lower() == header_key.lower():
+                        del headers[existing_key]
+                if not _is_openai_omitted_value(value):
+                    headers[header_key] = str(value)
 
         for key, value in extra_headers.items():
             if isinstance(value, NotGiven):

tests/models/test_openai_responses.py

@@ -3204,6 +3204,45 @@ async def fake_open(
     assert ws.close_calls == 1
 
 
+@pytest.mark.allow_call_model_methods
+@pytest.mark.asyncio
+async def test_websocket_model_prepare_websocket_request_includes_client_auth_headers():
+    client = AsyncOpenAI(api_key="test-key")
+    model = OpenAIResponsesWSModel(model="gpt-4", openai_client=client)
+
+    _frame, _ws_url, headers = await model._prepare_websocket_request(
+        {
+            "model": "gpt-4",
+            "input": "hi",
+            "stream": True,
+        }
+    )
+
+    assert "Authorization" not in client.default_headers
+    assert headers["Authorization"] == "Bearer test-key"
+
+
+@pytest.mark.allow_call_model_methods
+@pytest.mark.asyncio
+async def test_websocket_model_prepare_websocket_request_preserves_client_header_overrides():
+    client = AsyncOpenAI(
+        api_key="test-key",
+        default_headers={"authorization": "Bearer proxy-key"},
+    )
+    model = OpenAIResponsesWSModel(model="gpt-4", openai_client=client)
+
+    _frame, _ws_url, headers = await model._prepare_websocket_request(
+        {
+            "model": "gpt-4",
+            "input": "hi",
+            "stream": True,
+        }
+    )
+
+    assert headers["authorization"] == "Bearer proxy-key"
+    assert "Authorization" not in headers
+
+
 @pytest.mark.allow_call_model_methods
 @pytest.mark.asyncio
 async def test_websocket_model_prepare_websocket_request_omit_removes_inherited_header():