diff --git a/docs/docs/integrations/chat/xai.ipynb b/docs/docs/integrations/chat/xai.ipynb
index 22cc06d256f..7e9d37eb426 100644
--- a/docs/docs/integrations/chat/xai.ipynb
+++ b/docs/docs/integrations/chat/xai.ipynb
@@ -345,7 +345,7 @@
    "source": [
     "## API reference\n",
     "\n",
-    "For detailed documentation of all `ChatXAI` features and configurations, head to the API reference: https://python.langchain.com/api_reference/xai/chat_models/langchain_xai.chat_models.ChatXAI.html"
+    "For detailed documentation of all `ChatXAI` features and configurations, head to the [API reference](https://python.langchain.com/api_reference/xai/chat_models/langchain_xai.chat_models.ChatXAI.html)."
    ]
   }
  ],
diff --git a/docs/docs/integrations/providers/xai.ipynb b/docs/docs/integrations/providers/xai.ipynb
index 4840db40a53..8cf4de3104b 100644
--- a/docs/docs/integrations/providers/xai.ipynb
+++ b/docs/docs/integrations/providers/xai.ipynb
@@ -63,7 +63,7 @@
     "\n",
     "chat = ChatXAI(\n",
     "    # xai_api_key=\"YOUR_API_KEY\",\n",
-    "    model=\"grok-beta\",\n",
+    "    model=\"grok-4\",\n",
     ")\n",
     "\n",
     "# stream the response back from the model\n",
diff --git a/libs/partners/groq/langchain_groq/chat_models.py b/libs/partners/groq/langchain_groq/chat_models.py
index b4541a648ff..92c7b25c45f 100644
--- a/libs/partners/groq/langchain_groq/chat_models.py
+++ b/libs/partners/groq/langchain_groq/chat_models.py
@@ -395,10 +395,10 @@ class ChatGroq(BaseChatModel):
     # Configure a custom httpx client. See the
     # [httpx documentation](https://www.python-httpx.org/api/#client) for more details.
     http_client: Union[Any, None] = None
-    """Optional httpx.Client."""
+    """Optional ``httpx.Client``."""
     http_async_client: Union[Any, None] = None
-    """Optional httpx.AsyncClient. Only used for async invocations. Must specify
-        http_client as well if you'd like a custom client for sync invocations."""
+    """Optional ``httpx.AsyncClient``. Only used for async invocations. Must specify
+        ``http_client`` as well if you'd like a custom client for sync invocations."""
 
     model_config = ConfigDict(
         populate_by_name=True,
diff --git a/libs/partners/openai/langchain_openai/chat_models/azure.py b/libs/partners/openai/langchain_openai/chat_models/azure.py
index 2c85c892955..9f62b875675 100644
--- a/libs/partners/openai/langchain_openai/chat_models/azure.py
+++ b/libs/partners/openai/langchain_openai/chat_models/azure.py
@@ -76,13 +76,13 @@ class AzureChatOpenAI(BaseChatOpenAI):
             Max number of retries.
         organization: Optional[str]
             OpenAI organization ID. If not passed in will be read from env
-            var OPENAI_ORG_ID.
+            var ``OPENAI_ORG_ID``.
         model: Optional[str]
             The name of the underlying OpenAI model. Used for tracing and token
-            counting. Does not affect completion. E.g. "gpt-4", "gpt-35-turbo", etc.
+            counting. Does not affect completion. E.g. ``'gpt-4'``, ``'gpt-35-turbo'``, etc.
         model_version: Optional[str]
             The version of the underlying OpenAI model. Used for tracing and token
-            counting. Does not affect completion. E.g., "0125", "0125-preview", etc.
+            counting. Does not affect completion. E.g., ``'0125'``, ``'0125-preview'``, etc.
 
     See full list of supported init args and their descriptions in the params section.
 
diff --git a/libs/partners/openai/langchain_openai/chat_models/base.py b/libs/partners/openai/langchain_openai/chat_models/base.py
index b2488031931..bd436c36eea 100644
--- a/libs/partners/openai/langchain_openai/chat_models/base.py
+++ b/libs/partners/openai/langchain_openai/chat_models/base.py
@@ -542,12 +542,13 @@ class BaseChatOpenAI(BaseChatModel):
     # Configure a custom httpx client. See the
     # [httpx documentation](https://www.python-httpx.org/api/#client) for more details.
     http_client: Union[Any, None] = Field(default=None, exclude=True)
-    """Optional httpx.Client. Only used for sync invocations. Must specify 
-        http_async_client as well if you'd like a custom client for async invocations.
+    """Optional ``httpx.Client``. Only used for sync invocations. Must specify 
+        ``http_async_client`` as well if you'd like a custom client for async
+        invocations.
     """
     http_async_client: Union[Any, None] = Field(default=None, exclude=True)
     """Optional httpx.AsyncClient. Only used for async invocations. Must specify 
-        http_client as well if you'd like a custom client for sync invocations."""
+        ``http_client`` as well if you'd like a custom client for sync invocations."""
     stop: Optional[Union[list[str], str]] = Field(default=None, alias="stop_sequences")
     """Default stop sequences."""
     extra_body: Optional[Mapping[str, Any]] = None
@@ -588,8 +589,8 @@ class BaseChatOpenAI(BaseChatModel):
     """
 
     service_tier: Optional[str] = None
-    """Latency tier for request. Options are 'auto', 'default', or 'flex'. Relevant
-    for users of OpenAI's scale tier service.
+    """Latency tier for request. Options are ``'auto'``, ``'default'``, or ``'flex'``.
+    Relevant for users of OpenAI's scale tier service.
     """
 
     store: Optional[bool] = None
@@ -600,8 +601,8 @@ class BaseChatOpenAI(BaseChatModel):
     """
 
     truncation: Optional[str] = None
-    """Truncation strategy (Responses API). Can be ``"auto"`` or ``"disabled"``
-    (default). If ``"auto"``, model may drop input items from the middle of the
+    """Truncation strategy (Responses API). Can be ``'auto'`` or ``'disabled'``
+    (default). If ``'auto'``, model may drop input items from the middle of the
     message sequence to fit the context window.
 
     .. versionadded:: 0.3.24
@@ -1451,7 +1452,7 @@ class BaseChatOpenAI(BaseChatModel):
             Sequence[Union[dict[str, Any], type, Callable, BaseTool]]
         ] = None,
     ) -> int:
-        """Calculate num tokens for gpt-3.5-turbo and gpt-4 with tiktoken package.
+        """Calculate num tokens for ``gpt-3.5-turbo`` and ``gpt-4`` with ``tiktoken`` package.
 
         **Requirements**: You must have the ``pillow`` installed if you want to count
         image tokens if you are specifying the image as a base64 string, and you must
@@ -1459,14 +1460,13 @@ class BaseChatOpenAI(BaseChatModel):
         as a URL. If these aren't installed image inputs will be ignored in token
         counting.
 
-        OpenAI reference: https://github.com/openai/openai-cookbook/blob/
-        main/examples/How_to_format_inputs_to_ChatGPT_models.ipynb
+        `OpenAI reference <https://github.com/openai/openai-cookbook/blob/main/examples/How_to_format_inputs_to_ChatGPT_models.ipynb>`__
 
         Args:
             messages: The message inputs to tokenize.
             tools: If provided, sequence of dict, BaseModel, function, or BaseTools
                 to be converted to tool schemas.
-        """
+        """  # noqa: E501
         # TODO: Count bound tools as part of input.
         if tools is not None:
             warnings.warn(
@@ -2036,13 +2036,13 @@ class ChatOpenAI(BaseChatOpenAI):  # type: ignore[override]
         max_retries: Optional[int]
             Max number of retries.
         api_key: Optional[str]
-            OpenAI API key. If not passed in will be read from env var OPENAI_API_KEY.
+            OpenAI API key. If not passed in will be read from env var ``OPENAI_API_KEY``.
         base_url: Optional[str]
             Base URL for API requests. Only specify if using a proxy or service
             emulator.
         organization: Optional[str]
             OpenAI organization ID. If not passed in will be read from env
-            var OPENAI_ORG_ID.
+            var ``OPENAI_ORG_ID``.
 
         See full list of supported init args and their descriptions in the params section.
 
diff --git a/libs/partners/openai/langchain_openai/embeddings/base.py b/libs/partners/openai/langchain_openai/embeddings/base.py
index c23a466cff9..212c6385b04 100644
--- a/libs/partners/openai/langchain_openai/embeddings/base.py
+++ b/libs/partners/openai/langchain_openai/embeddings/base.py
@@ -93,14 +93,14 @@ class OpenAIEmbeddings(BaseModel, Embeddings):
             Name of OpenAI model to use.
         dimensions: Optional[int] = None
             The number of dimensions the resulting output embeddings should have.
-            Only supported in `text-embedding-3` and later models.
+            Only supported in ``'text-embedding-3'`` and later models.
 
     Key init args — client params:
         api_key: Optional[SecretStr] = None
             OpenAI API key.
         organization: Optional[str] = None
             OpenAI organization ID. If not passed in will be read
-            from env var OPENAI_ORG_ID.
+            from env var ``OPENAI_ORG_ID``.
         max_retries: int = 2
             Maximum number of retries to make when generating.
         request_timeout: Optional[Union[float, Tuple[float, float], Any]] = None
@@ -194,14 +194,14 @@ class OpenAIEmbeddings(BaseModel, Embeddings):
     openai_api_key: Optional[SecretStr] = Field(
         alias="api_key", default_factory=secret_from_env("OPENAI_API_KEY", default=None)
     )
-    """Automatically inferred from env var `OPENAI_API_KEY` if not provided."""
+    """Automatically inferred from env var ``OPENAI_API_KEY`` if not provided."""
     openai_organization: Optional[str] = Field(
         alias="organization",
         default_factory=from_env(
             ["OPENAI_ORG_ID", "OPENAI_ORGANIZATION"], default=None
         ),
     )
-    """Automatically inferred from env var `OPENAI_ORG_ID` if not provided."""
+    """Automatically inferred from env var ``OPENAI_ORG_ID`` if not provided."""
     allowed_special: Union[Literal["all"], set[str], None] = None
     disallowed_special: Union[Literal["all"], set[str], Sequence[str], None] = None
     chunk_size: int = 1000
@@ -211,12 +211,12 @@ class OpenAIEmbeddings(BaseModel, Embeddings):
     request_timeout: Optional[Union[float, tuple[float, float], Any]] = Field(
         default=None, alias="timeout"
     )
-    """Timeout for requests to OpenAI completion API. Can be float, httpx.Timeout or
+    """Timeout for requests to OpenAI completion API. Can be float, ``httpx.Timeout`` or
         None."""
     headers: Any = None
     tiktoken_enabled: bool = True
     """Set this to False for non-OpenAI implementations of the embeddings API, e.g.
-    the `--extensions openai` extension for `text-generation-webui`"""
+    the ``--extensions openai`` extension for ``text-generation-webui``"""
     tiktoken_model_name: Optional[str] = None
     """The model name to pass to tiktoken when using this class.
     Tiktoken is used to count the number of tokens in documents to constrain
@@ -243,12 +243,13 @@ class OpenAIEmbeddings(BaseModel, Embeddings):
     retry_max_seconds: int = 20
     """Max number of seconds to wait between retries"""
     http_client: Union[Any, None] = None
-    """Optional httpx.Client. Only used for sync invocations. Must specify
-        http_async_client as well if you'd like a custom client for async invocations.
+    """Optional ``httpx.Client``. Only used for sync invocations. Must specify
+        ``http_async_client`` as well if you'd like a custom client for async
+        invocations.
     """
     http_async_client: Union[Any, None] = None
-    """Optional httpx.AsyncClient. Only used for async invocations. Must specify
-        http_client as well if you'd like a custom client for sync invocations."""
+    """Optional ``httpx.AsyncClient``. Only used for async invocations. Must specify
+        ``http_client`` as well if you'd like a custom client for sync invocations."""
     check_embedding_ctx_length: bool = True
     """Whether to check the token length of inputs and automatically split inputs
         longer than embedding_ctx_length."""
@@ -289,8 +290,7 @@ class OpenAIEmbeddings(BaseModel, Embeddings):
         """Validate that api key and python package exists in environment."""
         if self.openai_api_type in ("azure", "azure_ad", "azuread"):
             raise ValueError(
-                "If you are using Azure, "
-                "please use the `AzureOpenAIEmbeddings` class."
+                "If you are using Azure, please use the `AzureOpenAIEmbeddings` class."
             )
         client_params: dict = {
             "api_key": (
diff --git a/libs/partners/openai/langchain_openai/llms/base.py b/libs/partners/openai/langchain_openai/llms/base.py
index e22b7b01712..b4ee88ee327 100644
--- a/libs/partners/openai/langchain_openai/llms/base.py
+++ b/libs/partners/openai/langchain_openai/llms/base.py
@@ -76,7 +76,7 @@ class BaseOpenAI(BaseLLM):
     openai_api_key: Optional[SecretStr] = Field(
         alias="api_key", default_factory=secret_from_env("OPENAI_API_KEY", default=None)
     )
-    """Automatically inferred from env var `OPENAI_API_KEY` if not provided."""
+    """Automatically inferred from env var ``OPENAI_API_KEY`` if not provided."""
     openai_api_base: Optional[str] = Field(
         alias="base_url", default_factory=from_env("OPENAI_API_BASE", default=None)
     )
@@ -88,7 +88,7 @@ class BaseOpenAI(BaseLLM):
             ["OPENAI_ORG_ID", "OPENAI_ORGANIZATION"], default=None
         ),
     )
-    """Automatically inferred from env var `OPENAI_ORG_ID` if not provided."""
+    """Automatically inferred from env var ``OPENAI_ORG_ID`` if not provided."""
     # to support explicit proxy for OpenAI
     openai_proxy: Optional[str] = Field(
         default_factory=from_env("OPENAI_PROXY", default=None)
@@ -130,12 +130,13 @@ class BaseOpenAI(BaseLLM):
     # Configure a custom httpx client. See the
     # [httpx documentation](https://www.python-httpx.org/api/#client) for more details.
     http_client: Union[Any, None] = None
-    """Optional httpx.Client. Only used for sync invocations. Must specify 
-        http_async_client as well if you'd like a custom client for async invocations.
+    """Optional ``httpx.Client``. Only used for sync invocations. Must specify 
+        ``http_async_client`` as well if you'd like a custom client for async
+        invocations.
     """
     http_async_client: Union[Any, None] = None
-    """Optional httpx.AsyncClient. Only used for async invocations. Must specify 
-        http_client as well if you'd like a custom client for sync invocations."""
+    """Optional ``httpx.AsyncClient``. Only used for async invocations. Must specify 
+        ``http_client`` as well if you'd like a custom client for sync invocations."""
     extra_body: Optional[Mapping[str, Any]] = None
     """Optional additional JSON properties to include in the request parameters when
     making requests to OpenAI compatible APIs, such as vLLM."""
@@ -606,13 +607,13 @@ class OpenAI(BaseOpenAI):
         max_retries: int
             Max number of retries.
         api_key: Optional[str]
-            OpenAI API key. If not passed in will be read from env var OPENAI_API_KEY.
+            OpenAI API key. If not passed in will be read from env var ``OPENAI_API_KEY``.
         base_url: Optional[str]
             Base URL for API requests. Only specify if using a proxy or service
             emulator.
         organization: Optional[str]
             OpenAI organization ID. If not passed in will be read from env
-            var OPENAI_ORG_ID.
+            var ``OPENAI_ORG_ID``.
 
     See full list of supported init args and their descriptions in the params section.
 
diff --git a/libs/partners/xai/langchain_xai/chat_models.py b/libs/partners/xai/langchain_xai/chat_models.py
index 03235f1906b..4c47dba9151 100644
--- a/libs/partners/xai/langchain_xai/chat_models.py
+++ b/libs/partners/xai/langchain_xai/chat_models.py
@@ -29,6 +29,9 @@ _DictOrPydantic = Union[dict, _BM]
 class ChatXAI(BaseChatOpenAI):  # type: ignore[override]
     r"""ChatXAI chat model.
 
+    Refer to `xAI's documentation <https://docs.x.ai/docs/api-reference#chat-completions>`__
+    for more nuanced details on the API's behavior and supported parameters.
+
     Setup:
         Install ``langchain-xai`` and set environment variable ``XAI_API_KEY``.
 
@@ -42,9 +45,12 @@ class ChatXAI(BaseChatOpenAI):  # type: ignore[override]
         model: str
             Name of model to use.
         temperature: float
-            Sampling temperature.
+            Sampling temperature between ``0`` and ``2``. Higher values mean more random completions,
+            while lower values (like ``0.2``) mean more focused and deterministic completions.
+            (Default: ``1``.)
         max_tokens: Optional[int]
-            Max number of tokens to generate.
+            Max number of tokens to generate. Refer to your `model's documentation <https://docs.x.ai/docs/models#model-pricing>`__
+            for the maximum number of tokens it can generate.
         logprobs: Optional[bool]
             Whether to return logprobs.
 
@@ -62,7 +68,7 @@ class ChatXAI(BaseChatOpenAI):  # type: ignore[override]
             from langchain_xai import ChatXAI
 
             llm = ChatXAI(
-                model="grok-beta",
+                model="grok-4",
                 temperature=0,
                 max_tokens=None,
                 timeout=None,
@@ -89,7 +95,7 @@ class ChatXAI(BaseChatOpenAI):  # type: ignore[override]
                 content="J'adore la programmation.",
                 response_metadata={
                     'token_usage': {'completion_tokens': 9, 'prompt_tokens': 32, 'total_tokens': 41},
-                    'model_name': 'grok-beta',
+                    'model_name': 'grok-4',
                     'system_fingerprint': None,
                     'finish_reason': 'stop',
                     'logprobs': None
@@ -113,7 +119,7 @@ class ChatXAI(BaseChatOpenAI):  # type: ignore[override]
             content=' programm' id='run-1bc996b5-293f-4114-96a1-e0f755c05eb9'
             content='ation' id='run-1bc996b5-293f-4114-96a1-e0f755c05eb9'
             content='.' id='run-1bc996b5-293f-4114-96a1-e0f755c05eb9'
-            content='' response_metadata={'finish_reason': 'stop', 'model_name': 'grok-beta'} id='run-1bc996b5-293f-4114-96a1-e0f755c05eb9'
+            content='' response_metadata={'finish_reason': 'stop', 'model_name': 'grok-4'} id='run-1bc996b5-293f-4114-96a1-e0f755c05eb9'
 
 
     Async:
@@ -133,7 +139,7 @@ class ChatXAI(BaseChatOpenAI):  # type: ignore[override]
                 content="J'adore la programmation.",
                 response_metadata={
                     'token_usage': {'completion_tokens': 9, 'prompt_tokens': 32, 'total_tokens': 41},
-                    'model_name': 'grok-beta',
+                    'model_name': 'grok-4',
                     'system_fingerprint': None,
                     'finish_reason': 'stop',
                     'logprobs': None
@@ -141,12 +147,39 @@ class ChatXAI(BaseChatOpenAI):  # type: ignore[override]
                 id='run-09371a11-7f72-4c53-8e7c-9de5c238b34c-0',
                 usage_metadata={'input_tokens': 32, 'output_tokens': 9, 'total_tokens': 41})
 
-    Tool calling:
+    Reasoning:
+        `Certain xAI models <https://docs.x.ai/docs/models#model-pricing>`__ support reasoning,
+        which allows the model to provide reasoning content along with the response.
+
+        If provided, reasoning content is returned under the ``additional_kwargs`` field of the
+        AIMessage or AIMessageChunk.
+
+        If supported, reasoning effort can be specified in the model constructor's ``extra_body``
+        argument, which will control the amount of reasoning the model does. The value can be one of
+        ``'low'`` or ``'high'``.
+
+        .. code-block:: python
+
+            model = ChatXAI(
+                model="grok-3-mini",
+                extra_body={"reasoning_effort": "high"},
+            )
+
+        .. note::
+            As of 2025-07-10, ``reasoning_content`` is only returned in Grok 3 models, such as
+            `Grok 3 Mini <https://docs.x.ai/docs/models/grok-3-mini>`__.
+
+        .. note::
+            Note that in `Grok 4 <https://docs.x.ai/docs/models/grok-4-0709>`__, as of 2025-07-10,
+            reasoning is not exposed in ``reasoning_content`` (other than initial ``'Thinking...'`` text),
+            reasoning cannot be disabled, and the ``reasoning_effort`` cannot be specified.
+
+    Tool calling / function calling:
         .. code-block:: python
 
             from pydantic import BaseModel, Field
 
-            llm = ChatXAI(model="grok-beta")
+            llm = ChatXAI(model="grok-4")
 
             class GetWeather(BaseModel):
                 '''Get the current weather in a given location'''
@@ -168,7 +201,6 @@ class ChatXAI(BaseChatOpenAI):  # type: ignore[override]
             )
             ai_msg.tool_calls
 
-
         .. code-block:: python
 
             [
@@ -186,6 +218,67 @@ class ChatXAI(BaseChatOpenAI):  # type: ignore[override]
                 }
             ]
 
+        .. note::
+            With stream response, the tool / function call will be returned in whole in a
+            single chunk, instead of being streamed across chunks.
+
+        Tool choice can be controlled by setting the ``tool_choice`` parameter in the model
+        constructor's ``extra_body`` argument. For example, to disable tool / function calling:
+        .. code-block:: python
+
+            llm = ChatXAI(model="grok-4", extra_body={"tool_choice": "none"})
+
+        To require that the model always calls a tool / function, set ``tool_choice`` to ``'required'``:
+
+        .. code-block:: python
+
+            llm = ChatXAI(model="grok-4", extra_body={"tool_choice": "required"})
+
+        To specify a tool / function to call, set ``tool_choice`` to the name of the tool / function:
+
+        .. code-block:: python
+
+            from pydantic import BaseModel, Field
+
+            llm = ChatXAI(
+                model="grok-4",
+                extra_body={
+                    "tool_choice": {"type": "function", "function": {"name": "GetWeather"}}
+                },
+            )
+
+            class GetWeather(BaseModel):
+                \"\"\"Get the current weather in a given location\"\"\"
+
+                location: str = Field(..., description='The city and state, e.g. San Francisco, CA')
+
+
+            class GetPopulation(BaseModel):
+                \"\"\"Get the current population in a given location\"\"\"
+
+                location: str = Field(..., description='The city and state, e.g. San Francisco, CA')
+
+
+            llm_with_tools = llm.bind_tools([GetWeather, GetPopulation])
+            ai_msg = llm_with_tools.invoke(
+                "Which city is bigger: LA or NY?",
+            )
+            ai_msg.tool_calls
+
+        The resulting tool call would be:
+
+        .. code-block:: python
+
+            [{'name': 'GetWeather',
+            'args': {'location': 'Los Angeles, CA'},
+            'id': 'call_81668711',
+            'type': 'tool_call'}]
+
+    Parallel tool calling / parallel function calling:
+        By default, parallel tool / function calling is enabled, so you can process
+        multiple function calls in one request/response cycle. When two or more tool calls
+        are required, all of the tool call requests will be included in the response body.
+
     Structured output:
         .. code-block:: python
 
@@ -222,7 +315,7 @@ class ChatXAI(BaseChatOpenAI):  # type: ignore[override]
             from langchain_xai import ChatXAI
 
             llm = ChatXAI(
-                model="grok-3-latest",
+                model="grok-4",
                 search_parameters={
                     "mode": "auto",
                     # Example optional parameters below:
@@ -234,6 +327,10 @@ class ChatXAI(BaseChatOpenAI):  # type: ignore[override]
 
             llm.invoke("Provide me a digest of world news in the last 24 hours.")
 
+        .. note::
+            `Citations <https://docs.x.ai/docs/guides/live-search#returning-citations>`__
+            are only available in `Grok 3 <https://docs.x.ai/docs/models/grok-3>`__.
+
     Token usage:
         .. code-block:: python
 
@@ -275,7 +372,7 @@ class ChatXAI(BaseChatOpenAI):  # type: ignore[override]
                     'prompt_tokens': 19,
                     'total_tokens': 23
                     },
-                'model_name': 'grok-beta',
+                'model_name': 'grok-4',
                 'system_fingerprint': None,
                 'finish_reason': 'stop',
                 'logprobs': None
@@ -283,7 +380,7 @@ class ChatXAI(BaseChatOpenAI):  # type: ignore[override]
 
     """  # noqa: E501
 
-    model_name: str = Field(alias="model")
+    model_name: str = Field(default="grok-4", alias="model")
     """Model name to use."""
     xai_api_key: Optional[SecretStr] = Field(
         alias="api_key",
diff --git a/libs/partners/xai/tests/integration_tests/test_chat_models_standard.py b/libs/partners/xai/tests/integration_tests/test_chat_models_standard.py
index 67e5bd1707a..7004936a578 100644
--- a/libs/partners/xai/tests/integration_tests/test_chat_models_standard.py
+++ b/libs/partners/xai/tests/integration_tests/test_chat_models_standard.py
@@ -18,6 +18,10 @@ rate_limiter = InMemoryRateLimiter(
 )
 
 
+# Not using Grok 4 since it doesn't support reasoning params (effort) or returns
+# reasoning content.
+
+
 class TestXAIStandard(ChatModelIntegrationTests):
     @property
     def chat_model_class(self) -> type[BaseChatModel]:
@@ -25,6 +29,7 @@ class TestXAIStandard(ChatModelIntegrationTests):
 
     @property
     def chat_model_params(self) -> dict:
+        # TODO: bump to test new Grok once they implement other features
         return {
             "model": "grok-3",
             "rate_limiter": rate_limiter,
@@ -35,7 +40,7 @@ class TestXAIStandard(ChatModelIntegrationTests):
 def test_reasoning_content() -> None:
     """Test reasoning content."""
     chat_model = ChatXAI(
-        model="grok-3-mini-beta",
+        model="grok-3-mini",
         reasoning_effort="low",
     )
     response = chat_model.invoke("What is 3^3?")
@@ -52,7 +57,7 @@ def test_reasoning_content() -> None:
 
 def test_web_search() -> None:
     llm = ChatXAI(
-        model="grok-3-latest",
+        model="grok-3",
         search_parameters={"mode": "auto", "max_search_results": 3},
     )
 
diff --git a/libs/partners/xai/tests/unit_tests/test_chat_models.py b/libs/partners/xai/tests/unit_tests/test_chat_models.py
index e595d449893..78c7a495153 100644
--- a/libs/partners/xai/tests/unit_tests/test_chat_models.py
+++ b/libs/partners/xai/tests/unit_tests/test_chat_models.py
@@ -15,10 +15,12 @@ from langchain_openai.chat_models.base import (
 
 from langchain_xai import ChatXAI
 
+MODEL_NAME = "grok-4"
+
 
 def test_initialization() -> None:
     """Test chat model initialization."""
-    ChatXAI(model="grok-beta")
+    ChatXAI(model=MODEL_NAME)
 
 
 def test_xai_model_param() -> None:
@@ -34,7 +36,7 @@ def test_chat_xai_invalid_streaming_params() -> None:
     """Test that streaming correctly invokes on_llm_new_token callback."""
     with pytest.raises(ValueError):
         ChatXAI(
-            model="grok-beta",
+            model=MODEL_NAME,
             max_tokens=10,
             streaming=True,
             temperature=0,
@@ -45,17 +47,17 @@ def test_chat_xai_invalid_streaming_params() -> None:
 def test_chat_xai_extra_kwargs() -> None:
     """Test extra kwargs to chat xai."""
     # Check that foo is saved in extra_kwargs.
-    llm = ChatXAI(model="grok-beta", foo=3, max_tokens=10)  # type: ignore[call-arg]
+    llm = ChatXAI(model=MODEL_NAME, foo=3, max_tokens=10)  # type: ignore[call-arg]
     assert llm.max_tokens == 10
     assert llm.model_kwargs == {"foo": 3}
 
     # Test that if extra_kwargs are provided, they are added to it.
-    llm = ChatXAI(model="grok-beta", foo=3, model_kwargs={"bar": 2})  # type: ignore[call-arg]
+    llm = ChatXAI(model=MODEL_NAME, foo=3, model_kwargs={"bar": 2})  # type: ignore[call-arg]
     assert llm.model_kwargs == {"foo": 3, "bar": 2}
 
     # Test that if provided twice it errors
     with pytest.raises(ValueError):
-        ChatXAI(model="grok-beta", foo=3, model_kwargs={"foo": 2})  # type: ignore[call-arg]
+        ChatXAI(model=MODEL_NAME, foo=3, model_kwargs={"foo": 2})  # type: ignore[call-arg]
 
 
 def test_function_dict_to_message_function_message() -> None:
diff --git a/libs/partners/xai/tests/unit_tests/test_secrets.py b/libs/partners/xai/tests/unit_tests/test_secrets.py
index bcb83e774ff..7156c693f9e 100644
--- a/libs/partners/xai/tests/unit_tests/test_secrets.py
+++ b/libs/partners/xai/tests/unit_tests/test_secrets.py
@@ -1,7 +1,9 @@
 from langchain_xai import ChatXAI
 
+MODEL_NAME = "grok-4"
+
 
 def test_chat_xai_secrets() -> None:
-    o = ChatXAI(model="grok-beta", xai_api_key="foo")  # type: ignore[call-arg]
+    o = ChatXAI(model=MODEL_NAME, xai_api_key="foo")  # type: ignore[call-arg]
     s = str(o)
     assert "foo" not in s