From 8fec4e7ceee2c368b068c49f9fed453276e210e7 Mon Sep 17 00:00:00 2001
From: Thomas <67928676+thomas-bartlett@users.noreply.github.com>
Date: Sun, 19 Apr 2026 11:06:26 -0400
Subject: [PATCH] fix(openai): infer azure chat profiles from model name
 (#36858)

---
 .../langchain_openai/chat_models/azure.py     |  4 +
 .../unit_tests/chat_models/test_azure.py      | 91 +++++++++++++++++++
 2 files changed, 95 insertions(+)

diff --git a/libs/partners/openai/langchain_openai/chat_models/azure.py b/libs/partners/openai/langchain_openai/chat_models/azure.py
index 240d6c876f3..797901cfd2b 100644
--- a/libs/partners/openai/langchain_openai/chat_models/azure.py
+++ b/libs/partners/openai/langchain_openai/chat_models/azure.py
@@ -705,6 +705,10 @@ class AzureChatOpenAI(BaseChatOpenAI):
         return self
 
     def _resolve_model_profile(self) -> ModelProfile | None:
+        if (self.model_name is not None) and (
+            profile := _get_default_model_profile(self.model_name) or None
+        ):
+            return profile
         if self.deployment_name is not None:
             return _get_default_model_profile(self.deployment_name) or None
         return None
diff --git a/libs/partners/openai/tests/unit_tests/chat_models/test_azure.py b/libs/partners/openai/tests/unit_tests/chat_models/test_azure.py
index b81b5d82ff0..437b44414d2 100644
--- a/libs/partners/openai/tests/unit_tests/chat_models/test_azure.py
+++ b/libs/partners/openai/tests/unit_tests/chat_models/test_azure.py
@@ -16,6 +16,7 @@ def test_initialize_azure_openai() -> None:
         azure_deployment="35-turbo-dev",
         openai_api_version="2023-05-15",
         azure_endpoint="my-base-url",
+        api_key=SecretStr("test"),
     )
     assert llm.deployment_name == "35-turbo-dev"
     assert llm.openai_api_version == "2023-05-15"
@@ -45,6 +46,92 @@ def test_initialize_more() -> None:
     assert ls_params.get("ls_model_name") == "gpt-35-turbo-0125"
 
 
+def test_profile_resolves_from_model_name() -> None:
+    llm = AzureChatOpenAI(
+        model="gpt-4o",
+        azure_endpoint="my-base-url",
+        api_key=SecretStr("test"),
+        api_version="2023-05-15",
+    )
+
+    assert llm.profile
+    assert llm.profile["name"] == "GPT-4o"
+    assert llm.profile["max_input_tokens"] == 128_000
+
+
+def test_profile_resolves_from_model_name_with_custom_deployment_alias() -> None:
+    llm = AzureChatOpenAI(
+        model="gpt-4o",
+        azure_deployment="35-turbo-dev",
+        azure_endpoint="my-base-url",
+        api_key=SecretStr("test"),
+        api_version="2023-05-15",
+    )
+
+    assert llm.profile
+    assert llm.profile["name"] == "GPT-4o"
+
+
+def test_profile_prefers_model_name_over_known_deployment_name() -> None:
+    llm = AzureChatOpenAI(
+        model="gpt-4o",
+        azure_deployment="gpt-4",
+        azure_endpoint="my-base-url",
+        api_key=SecretStr("test"),
+        api_version="2023-05-15",
+    )
+
+    assert llm.profile
+    assert llm.profile["name"] == "GPT-4o"
+
+
+def test_profile_falls_back_to_deployment_name_with_unknown_model() -> None:
+    llm = AzureChatOpenAI(
+        model="unknown-model",
+        azure_deployment="gpt-4o",
+        azure_endpoint="my-base-url",
+        api_key=SecretStr("test"),
+        api_version="2023-05-15",
+    )
+
+    assert llm.profile
+
+
+def test_profile_resolves_from_deployment_name_without_model() -> None:
+    llm = AzureChatOpenAI(
+        azure_deployment="gpt-4o",
+        azure_endpoint="my-base-url",
+        api_key=SecretStr("test"),
+        api_version="2023-05-15",
+    )
+
+    assert llm.profile
+    assert llm.profile["name"] == "GPT-4o"
+
+
+def test_profile_respects_explicit_profile() -> None:
+    llm = AzureChatOpenAI(
+        model="gpt-4o",
+        azure_endpoint="my-base-url",
+        api_key=SecretStr("test"),
+        api_version="2023-05-15",
+        profile={"tool_calling": False},
+    )
+
+    assert llm.profile == {"tool_calling": False}
+
+
+def test_profile_is_none_for_unknown_deployment_without_model() -> None:
+    llm = AzureChatOpenAI(
+        azure_deployment="unknown-deployment",
+        azure_endpoint="my-base-url",
+        api_key=SecretStr("test"),
+        api_version="2023-05-15",
+    )
+
+    assert llm.profile is None
+
+
 def test_initialize_azure_openai_with_openai_api_base_set() -> None:
     with mock.patch.dict(os.environ, {"OPENAI_API_BASE": "https://api.openai.com"}):
         llm = AzureChatOpenAI(  # type: ignore[call-arg, call-arg]
@@ -79,6 +166,7 @@ def test_structured_output_old_model() -> None:
             azure_deployment="35-turbo-dev",
             openai_api_version="2023-05-15",
             azure_endpoint="my-base-url",
+            api_key=SecretStr("test"),
         ).with_structured_output(Output)
 
     # assert tool calling was used instead of json_schema
@@ -91,6 +179,7 @@ def test_max_completion_tokens_in_payload() -> None:
         azure_deployment="o1-mini",
         api_version="2024-12-01-preview",
         azure_endpoint="my-base-url",
+        api_key=SecretStr("test"),
         model_kwargs={"max_completion_tokens": 300},
     )
     messages = [HumanMessage("Hello")]
@@ -148,6 +237,7 @@ def test_max_completion_tokens_parameter() -> None:
         azure_deployment="gpt-5",
         api_version="2024-12-01-preview",
         azure_endpoint="my-base-url",
+        api_key=SecretStr("test"),
         max_completion_tokens=1500,
     )
     messages = [HumanMessage("Hello")]
@@ -165,6 +255,7 @@ def test_max_tokens_converted_to_max_completion_tokens() -> None:
         azure_deployment="gpt-5",
         api_version="2024-12-01-preview",
         azure_endpoint="my-base-url",
+        api_key=SecretStr("test"),
         max_tokens=1000,  # type: ignore[call-arg]
     )
     messages = [HumanMessage("Hello")]