From f4e83e0ad8d12bec889fb3b96ffedec183bf5267 Mon Sep 17 00:00:00 2001
From: Christophe Bornet <cbornet@hotmail.com>
Date: Mon, 8 Sep 2025 17:44:15 +0200
Subject: [PATCH] chore(core): fix some docstrings (from DOC preview rule)
 (#32833)

* Add `Raises` sections
* Add `Returns` sections
* Add `Yields` sections

---------

Co-authored-by: Mason Daugherty <mason@langchain.dev>
---
 .../langchain_core/_api/beta_decorator.py     |   3 +
 libs/core/langchain_core/_api/deprecation.py  |  12 ++
 libs/core/langchain_core/_api/path.py         |  21 ++-
 libs/core/langchain_core/_import_utils.py     |   7 +
 libs/core/langchain_core/agents.py            |   8 +-
 libs/core/langchain_core/callbacks/base.py    |   2 +-
 libs/core/langchain_core/callbacks/manager.py |  66 ++++----
 libs/core/langchain_core/callbacks/usage.py   |   3 +
 libs/core/langchain_core/chat_history.py      |   3 +
 .../langchain_core/document_loaders/base.py   |  30 +++-
 .../document_loaders/langsmith.py             |   3 +
 libs/core/langchain_core/documents/base.py    |  40 ++++-
 .../langchain_core/example_selectors/base.py  |  12 ++
 libs/core/langchain_core/exceptions.py        |   7 +
 libs/core/langchain_core/indexing/api.py      |   9 +
 libs/core/langchain_core/indexing/base.py     |  11 +-
 .../core/langchain_core/indexing/in_memory.py |  26 ++-
 .../langchain_core/language_models/base.py    |   6 +
 .../language_models/chat_models.py            |  65 ++++++-
 .../language_models/fake_chat_models.py       |  12 +-
 .../langchain_core/language_models/llms.py    |  47 ++++-
 libs/core/langchain_core/load/load.py         |  16 +-
 libs/core/langchain_core/load/serializable.py |  17 +-
 libs/core/langchain_core/messages/ai.py       |  36 +++-
 libs/core/langchain_core/messages/base.py     |  12 +-
 .../langchain_core/messages/content_blocks.py |  25 ++-
 libs/core/langchain_core/messages/tool.py     |  27 ++-
 libs/core/langchain_core/messages/utils.py    |   4 +
 .../langchain_core/output_parsers/list.py     |  26 +--
 .../output_parsers/openai_functions.py        |   3 +
 .../output_parsers/openai_tools.py            |   7 +-
 .../langchain_core/output_parsers/pydantic.py |   4 +
 .../langchain_core/output_parsers/string.py   |   3 +-
 .../core/langchain_core/output_parsers/xml.py |   3 -
 .../langchain_core/outputs/chat_generation.py |  25 ++-
 .../core/langchain_core/outputs/generation.py |  17 +-
 .../core/langchain_core/outputs/llm_result.py |   9 +-
 libs/core/langchain_core/prompt_values.py     |  14 +-
 libs/core/langchain_core/prompts/base.py      |  11 +-
 libs/core/langchain_core/prompts/chat.py      |  34 +++-
 libs/core/langchain_core/prompts/dict.py      |  24 ++-
 libs/core/langchain_core/prompts/few_shot.py  |   4 +-
 .../prompts/few_shot_with_templates.py        |   6 +-
 libs/core/langchain_core/prompts/image.py     |  17 +-
 libs/core/langchain_core/prompts/message.py   |   8 +-
 libs/core/langchain_core/prompts/pipeline.py  |   6 +-
 libs/core/langchain_core/prompts/prompt.py    |  16 +-
 libs/core/langchain_core/prompts/string.py    |   6 +-
 .../core/langchain_core/prompts/structured.py |   7 +-
 libs/core/langchain_core/retrievers.py        |   1 +
 libs/core/langchain_core/runnables/base.py    | 160 +++++++++++++++---
 libs/core/langchain_core/runnables/branch.py  |  14 +-
 libs/core/langchain_core/runnables/config.py  |   9 +-
 .../langchain_core/runnables/configurable.py  |   6 +
 .../langchain_core/runnables/fallbacks.py     |  10 +-
 libs/core/langchain_core/runnables/graph.py   |  14 +-
 .../langchain_core/runnables/graph_ascii.py   |  33 +++-
 .../langchain_core/runnables/graph_png.py     |  18 +-
 .../langchain_core/runnables/passthrough.py   |  20 ++-
 libs/core/langchain_core/runnables/router.py  |   8 +-
 libs/core/langchain_core/runnables/utils.py   |  68 +++-----
 libs/core/langchain_core/stores.py            |  20 +--
 libs/core/langchain_core/tools/base.py        |  23 ++-
 libs/core/langchain_core/tools/convert.py     |  11 ++
 libs/core/langchain_core/tools/simple.py      |  38 ++++-
 libs/core/langchain_core/tools/structured.py  |  27 ++-
 libs/core/langchain_core/tracers/base.py      |   4 +-
 libs/core/langchain_core/tracers/context.py   |   6 +-
 libs/core/langchain_core/tracers/core.py      | 110 +++++++++---
 .../langchain_core/tracers/event_stream.py    |  31 +++-
 libs/core/langchain_core/tracers/langchain.py |   7 +-
 .../langchain_core/tracers/langchain_v1.py    |  12 +-
 .../core/langchain_core/tracers/log_stream.py |  56 +++++-
 libs/core/langchain_core/tracers/schemas.py   |   6 +-
 libs/core/langchain_core/utils/aiter.py       |  18 +-
 libs/core/langchain_core/utils/env.py         |   3 +
 .../langchain_core/utils/function_calling.py  |  21 ++-
 .../langchain_core/utils/interactive_env.py   |   6 +-
 libs/core/langchain_core/utils/iter.py        |  14 +-
 libs/core/langchain_core/utils/json.py        |   3 +
 libs/core/langchain_core/utils/json_schema.py |   7 +
 libs/core/langchain_core/utils/loading.py     |   6 +-
 libs/core/langchain_core/utils/mustache.py    |  37 ++--
 libs/core/langchain_core/utils/pydantic.py    |  36 +++-
 libs/core/langchain_core/utils/utils.py       |  30 +++-
 libs/core/langchain_core/vectorstores/base.py |   6 -
 .../langchain_core/vectorstores/in_memory.py  |   2 -
 87 files changed, 1281 insertions(+), 400 deletions(-)

diff --git a/libs/core/langchain_core/_api/beta_decorator.py b/libs/core/langchain_core/_api/beta_decorator.py
index 76955b435f4..786f371ad21 100644
--- a/libs/core/langchain_core/_api/beta_decorator.py
+++ b/libs/core/langchain_core/_api/beta_decorator.py
@@ -63,6 +63,9 @@ def beta(
         addendum : str, optional
             Additional text appended directly to the final message.
 
+    Returns:
+        A decorator which can be used to mark functions or classes as beta.
+
     Examples:
 
         .. code-block:: python
diff --git a/libs/core/langchain_core/_api/deprecation.py b/libs/core/langchain_core/_api/deprecation.py
index dc83afa2d17..7999d8a3216 100644
--- a/libs/core/langchain_core/_api/deprecation.py
+++ b/libs/core/langchain_core/_api/deprecation.py
@@ -129,6 +129,9 @@ def deprecated(
         package: str, optional
             The package of the deprecated object.
 
+    Returns:
+        A decorator to mark a function or class as deprecated.
+
     Examples:
 
         .. code-block:: python
@@ -544,6 +547,15 @@ def rename_parameter(
     is passed to *func*, a DeprecationWarning is emitted, and its value is
     used, even if *new* is also passed by keyword.
 
+    Args:
+        since: The version in which the parameter was renamed.
+        removal: The version in which the old parameter will be removed.
+        old: The old parameter name.
+        new: The new parameter name.
+
+    Returns:
+        A decorator indicating that a parameter was renamed.
+
     Example:
 
         .. code-block:: python
diff --git a/libs/core/langchain_core/_api/path.py b/libs/core/langchain_core/_api/path.py
index 0589ae44956..0d70b5a23a3 100644
--- a/libs/core/langchain_core/_api/path.py
+++ b/libs/core/langchain_core/_api/path.py
@@ -12,7 +12,15 @@ SEPARATOR = os.sep
 def get_relative_path(
     file: Union[Path, str], *, relative_to: Path = PACKAGE_DIR
 ) -> str:
-    """Get the path of the file as a relative path to the package directory."""
+    """Get the path of the file as a relative path to the package directory.
+
+    Args:
+        file: The file path to convert.
+        relative_to: The base path to make the file path relative to.
+
+    Returns:
+        The relative path as a string.
+    """
     if isinstance(file, str):
         file = Path(file)
     return str(file.relative_to(relative_to))
@@ -24,7 +32,16 @@ def as_import_path(
     suffix: Optional[str] = None,
     relative_to: Path = PACKAGE_DIR,
 ) -> str:
-    """Path of the file as a LangChain import exclude langchain top namespace."""
+    """Path of the file as a LangChain import exclude langchain top namespace.
+
+    Args:
+        file: The file path to convert.
+        suffix: An optional suffix to append to the import path.
+        relative_to: The base path to make the file path relative to.
+
+    Returns:
+        The import path as a string.
+    """
     if isinstance(file, str):
         file = Path(file)
     path = get_relative_path(file, relative_to=relative_to)
diff --git a/libs/core/langchain_core/_import_utils.py b/libs/core/langchain_core/_import_utils.py
index 6f4d0a5df2b..6e0ce0bbee9 100644
--- a/libs/core/langchain_core/_import_utils.py
+++ b/libs/core/langchain_core/_import_utils.py
@@ -17,6 +17,13 @@ def import_attr(
         module_name: The name of the module to import from. If None, the attribute
             is imported from the package itself.
         package: The name of the package where the module is located.
+
+    Raises:
+        ImportError: If the module cannot be found.
+        AttributeError: If the attribute does not exist in the module or package.
+
+    Returns:
+        The imported attribute.
     """
     if module_name == "__module__" or module_name is None:
         try:
diff --git a/libs/core/langchain_core/agents.py b/libs/core/langchain_core/agents.py
index 8fa3fde3888..dae02a86f13 100644
--- a/libs/core/langchain_core/agents.py
+++ b/libs/core/langchain_core/agents.py
@@ -86,7 +86,8 @@ class AgentAction(Serializable):
     def get_lc_namespace(cls) -> list[str]:
         """Get the namespace of the langchain object.
 
-        Default is ["langchain", "schema", "agent"].
+        Returns:
+            ``["langchain", "schema", "agent"]``
         """
         return ["langchain", "schema", "agent"]
 
@@ -155,14 +156,15 @@ class AgentFinish(Serializable):
 
     @classmethod
     def is_lc_serializable(cls) -> bool:
-        """Return whether or not the class is serializable."""
+        """Return True as this class is serializable."""
         return True
 
     @classmethod
     def get_lc_namespace(cls) -> list[str]:
         """Get the namespace of the langchain object.
 
-        Default namespace is ["langchain", "schema", "agent"].
+        Returns:
+            ``["langchain", "schema", "agent"]``
         """
         return ["langchain", "schema", "agent"]
 
diff --git a/libs/core/langchain_core/callbacks/base.py b/libs/core/langchain_core/callbacks/base.py
index 68c4e4a254b..3f3fd178cfd 100644
--- a/libs/core/langchain_core/callbacks/base.py
+++ b/libs/core/langchain_core/callbacks/base.py
@@ -922,7 +922,7 @@ class BaseCallbackManager(CallbackManagerMixin):
         self.inheritable_metadata = inheritable_metadata or {}
 
     def copy(self) -> Self:
-        """Copy the callback manager."""
+        """Return a copy of the callback manager."""
         return self.__class__(
             handlers=self.handlers.copy(),
             inheritable_handlers=self.inheritable_handlers.copy(),
diff --git a/libs/core/langchain_core/callbacks/manager.py b/libs/core/langchain_core/callbacks/manager.py
index 8498995f86d..4851a1c1c1d 100644
--- a/libs/core/langchain_core/callbacks/manager.py
+++ b/libs/core/langchain_core/callbacks/manager.py
@@ -88,8 +88,8 @@ def trace_as_chain_group(
         Must have ``LANGCHAIN_TRACING_V2`` env var set to true to see the trace in
         LangSmith.
 
-    Returns:
-        CallbackManagerForChainGroup: The callback manager for the chain group.
+    Yields:
+        The callback manager for the chain group.
 
     Example:
         .. code-block:: python
@@ -170,8 +170,8 @@ async def atrace_as_chain_group(
         metadata (dict[str, Any], optional): The metadata to apply to all runs.
             Defaults to None.
 
-    Returns:
-        AsyncCallbackManager: The async callback manager for the chain group.
+    Yields:
+        The async callback manager for the chain group.
 
     .. note:
         Must have ``LANGCHAIN_TRACING_V2`` env var set to true to see the trace in
@@ -519,15 +519,12 @@ class RunManager(BaseRunManager):
         self,
         text: str,
         **kwargs: Any,
-    ) -> Any:
+    ) -> None:
         """Run when a text is received.
 
         Args:
             text (str): The received text.
             **kwargs (Any): Additional keyword arguments.
-
-        Returns:
-            Any: The result of the callback.
         """
         if not self.handlers:
             return
@@ -607,16 +604,12 @@ class AsyncRunManager(BaseRunManager, ABC):
         self,
         text: str,
         **kwargs: Any,
-    ) -> Any:
+    ) -> None:
         """Run when a text is received.
 
         Args:
             text (str): The received text.
             **kwargs (Any): Additional keyword arguments.
-
-        Returns:
-            Any: The result of the callback.
-
         """
         if not self.handlers:
             return
@@ -914,16 +907,12 @@ class CallbackManagerForChainRun(ParentRunManager, ChainManagerMixin):
             **kwargs,
         )
 
-    def on_agent_action(self, action: AgentAction, **kwargs: Any) -> Any:
+    def on_agent_action(self, action: AgentAction, **kwargs: Any) -> None:
         """Run when agent action is received.
 
         Args:
             action (AgentAction): The agent action.
             **kwargs (Any): Additional keyword arguments.
-
-        Returns:
-            Any: The result of the callback.
-
         """
         if not self.handlers:
             return
@@ -938,16 +927,12 @@ class CallbackManagerForChainRun(ParentRunManager, ChainManagerMixin):
             **kwargs,
         )
 
-    def on_agent_finish(self, finish: AgentFinish, **kwargs: Any) -> Any:
+    def on_agent_finish(self, finish: AgentFinish, **kwargs: Any) -> None:
         """Run when agent finish is received.
 
         Args:
             finish (AgentFinish): The agent finish.
             **kwargs (Any): Additional keyword arguments.
-
-        Returns:
-            Any: The result of the callback.
-
         """
         if not self.handlers:
             return
@@ -1033,16 +1018,12 @@ class AsyncCallbackManagerForChainRun(AsyncParentRunManager, ChainManagerMixin):
             **kwargs,
         )
 
-    async def on_agent_action(self, action: AgentAction, **kwargs: Any) -> Any:
+    async def on_agent_action(self, action: AgentAction, **kwargs: Any) -> None:
         """Run when agent action is received.
 
         Args:
             action (AgentAction): The agent action.
             **kwargs (Any): Additional keyword arguments.
-
-        Returns:
-            Any: The result of the callback.
-
         """
         if not self.handlers:
             return
@@ -1057,16 +1038,12 @@ class AsyncCallbackManagerForChainRun(AsyncParentRunManager, ChainManagerMixin):
             **kwargs,
         )
 
-    async def on_agent_finish(self, finish: AgentFinish, **kwargs: Any) -> Any:
+    async def on_agent_finish(self, finish: AgentFinish, **kwargs: Any) -> None:
         """Run when agent finish is received.
 
         Args:
             finish (AgentFinish): The agent finish.
             **kwargs (Any): Additional keyword arguments.
-
-        Returns:
-            Any: The result of the callback.
-
         """
         if not self.handlers:
             return
@@ -1562,6 +1539,8 @@ class CallbackManager(BaseCallbackManager):
             parent_run_id (UUID, optional): The ID of the parent run. Defaults to None.
             **kwargs (Any): Additional keyword arguments.
 
+        Returns:
+            The callback manager for the retriever run.
         """
         if run_id is None:
             run_id = uuid.uuid4()
@@ -1608,6 +1587,9 @@ class CallbackManager(BaseCallbackManager):
             data: The data for the adhoc event.
             run_id: The ID of the run. Defaults to None.
 
+        Raises:
+            ValueError: If additional keyword arguments are passed.
+
         .. versionadded:: 0.2.14
 
         """
@@ -1710,8 +1692,8 @@ class CallbackManagerForChainGroup(CallbackManager):
         self.parent_run_manager = parent_run_manager
         self.ended = False
 
+    @override
     def copy(self) -> CallbackManagerForChainGroup:
-        """Copy the callback manager."""
         return self.__class__(
             handlers=self.handlers.copy(),
             inheritable_handlers=self.inheritable_handlers.copy(),
@@ -2099,6 +2081,9 @@ class AsyncCallbackManager(BaseCallbackManager):
             data: The data for the adhoc event.
             run_id: The ID of the run. Defaults to None.
 
+        Raises:
+            ValueError: If additional keyword arguments are passed.
+
         .. versionadded:: 0.2.14
         """
         if not self.handlers:
@@ -2249,7 +2234,7 @@ class AsyncCallbackManagerForChainGroup(AsyncCallbackManager):
         self.ended = False
 
     def copy(self) -> AsyncCallbackManagerForChainGroup:
-        """Copy the async callback manager."""
+        """Return a copy the async callback manager."""
         return self.__class__(
             handlers=self.handlers.copy(),
             inheritable_handlers=self.inheritable_handlers.copy(),
@@ -2385,6 +2370,9 @@ def _configure(
         local_metadata (Optional[dict[str, Any]], optional): The local metadata.
             Defaults to None.
 
+    Raises:
+        RuntimeError: If `LANGCHAIN_TRACING` is set but `LANGCHAIN_TRACING_V2` is not.
+
     Returns:
         T: The configured callback manager.
     """
@@ -2557,6 +2545,10 @@ async def adispatch_custom_event(
               this is not enforced.
         config: Optional config object. Mirrors the async API but not strictly needed.
 
+    Raises:
+        RuntimeError: If there is no parent run ID available to associate
+            the event with.
+
     Example:
 
         .. code-block:: python
@@ -2678,6 +2670,10 @@ def dispatch_custom_event(
               this is not enforced.
         config: Optional config object. Mirrors the async API but not strictly needed.
 
+    Raises:
+        RuntimeError: If there is no parent run ID available to associate
+            the event with.
+
     Example:
 
         .. code-block:: python
diff --git a/libs/core/langchain_core/callbacks/usage.py b/libs/core/langchain_core/callbacks/usage.py
index 0249cadec1f..497b6ff4912 100644
--- a/libs/core/langchain_core/callbacks/usage.py
+++ b/libs/core/langchain_core/callbacks/usage.py
@@ -101,6 +101,9 @@ def get_usage_metadata_callback(
         name (str): The name of the context variable. Defaults to
             ``'usage_metadata_callback'``.
 
+    Yields:
+        The usage metadata callback.
+
     Example:
         .. code-block:: python
 
diff --git a/libs/core/langchain_core/chat_history.py b/libs/core/langchain_core/chat_history.py
index 19138005162..0091b240b69 100644
--- a/libs/core/langchain_core/chat_history.py
+++ b/libs/core/langchain_core/chat_history.py
@@ -109,6 +109,9 @@ class BaseChatMessageHistory(ABC):
 
         In general, fetching messages may involve IO to the underlying
         persistence layer.
+
+        Returns:
+            The messages.
         """
         from langchain_core.runnables.config import run_in_executor
 
diff --git a/libs/core/langchain_core/document_loaders/base.py b/libs/core/langchain_core/document_loaders/base.py
index 0d4054c2b99..7208529da17 100644
--- a/libs/core/langchain_core/document_loaders/base.py
+++ b/libs/core/langchain_core/document_loaders/base.py
@@ -28,11 +28,19 @@ class BaseLoader(ABC):  # noqa: B024
     # Sub-classes should not implement this method directly. Instead, they
     # should implement the lazy load method.
     def load(self) -> list[Document]:
-        """Load data into Document objects."""
+        """Load data into Document objects.
+
+        Returns:
+            the documents.
+        """
         return list(self.lazy_load())
 
     async def aload(self) -> list[Document]:
-        """Load data into Document objects."""
+        """Load data into Document objects.
+
+        Returns:
+            the documents.
+        """
         return [document async for document in self.alazy_load()]
 
     def load_and_split(
@@ -44,7 +52,11 @@ class BaseLoader(ABC):  # noqa: B024
 
         Args:
             text_splitter: TextSplitter instance to use for splitting documents.
-              Defaults to RecursiveCharacterTextSplitter.
+                Defaults to RecursiveCharacterTextSplitter.
+
+        Raises:
+            ImportError: If langchain-text-splitters is not installed
+                and no text_splitter is provided.
 
         Returns:
             List of Documents.
@@ -69,14 +81,22 @@ class BaseLoader(ABC):  # noqa: B024
     # Attention: This method will be upgraded into an abstractmethod once it's
     #            implemented in all the existing subclasses.
     def lazy_load(self) -> Iterator[Document]:
-        """A lazy loader for Documents."""
+        """A lazy loader for Documents.
+
+        Yields:
+            the documents.
+        """
         if type(self).load != BaseLoader.load:
             return iter(self.load())
         msg = f"{self.__class__.__name__} does not implement lazy_load()"
         raise NotImplementedError(msg)
 
     async def alazy_load(self) -> AsyncIterator[Document]:
-        """A lazy loader for Documents."""
+        """A lazy loader for Documents.
+
+        Yields:
+            the documents.
+        """
         iterator = await run_in_executor(None, self.lazy_load)
         done = object()
         while True:
diff --git a/libs/core/langchain_core/document_loaders/langsmith.py b/libs/core/langchain_core/document_loaders/langsmith.py
index 67089f520a3..81d9f26c3db 100644
--- a/libs/core/langchain_core/document_loaders/langsmith.py
+++ b/libs/core/langchain_core/document_loaders/langsmith.py
@@ -84,6 +84,9 @@ class LangSmithLoader(BaseLoader):
             client: LangSmith Client. If not provided will be initialized from below args.
             client_kwargs: Keyword args to pass to LangSmith client init. Should only be
                 specified if ``client`` isn't.
+
+        Raises:
+            ValueError: If both ``client`` and ``client_kwargs`` are provided.
         """  # noqa: E501
         if client and client_kwargs:
             raise ValueError
diff --git a/libs/core/langchain_core/documents/base.py b/libs/core/langchain_core/documents/base.py
index 99ae9b62892..adc42ac0182 100644
--- a/libs/core/langchain_core/documents/base.py
+++ b/libs/core/langchain_core/documents/base.py
@@ -145,7 +145,14 @@ class Blob(BaseMedia):
         return values
 
     def as_string(self) -> str:
-        """Read data as a string."""
+        """Read data as a string.
+
+        Raises:
+            ValueError: If the blob cannot be represented as a string.
+
+        Returns:
+            The data as a string.
+        """
         if self.data is None and self.path:
             return Path(self.path).read_text(encoding=self.encoding)
         if isinstance(self.data, bytes):
@@ -156,7 +163,14 @@ class Blob(BaseMedia):
         raise ValueError(msg)
 
     def as_bytes(self) -> bytes:
-        """Read data as bytes."""
+        """Read data as bytes.
+
+        Raises:
+            ValueError: If the blob cannot be represented as bytes.
+
+        Returns:
+            The data as bytes.
+        """
         if isinstance(self.data, bytes):
             return self.data
         if isinstance(self.data, str):
@@ -168,7 +182,14 @@ class Blob(BaseMedia):
 
     @contextlib.contextmanager
     def as_bytes_io(self) -> Generator[Union[BytesIO, BufferedReader], None, None]:
-        """Read data as a byte stream."""
+        """Read data as a byte stream.
+
+        Raises:
+            NotImplementedError: If the blob cannot be represented as a byte stream.
+
+        Yields:
+            The data as a byte stream.
+        """
         if isinstance(self.data, bytes):
             yield BytesIO(self.data)
         elif self.data is None and self.path:
@@ -246,7 +267,7 @@ class Blob(BaseMedia):
         )
 
     def __repr__(self) -> str:
-        """Define the blob representation."""
+        """Return the blob representation."""
         str_repr = f"Blob {id(self)}"
         if self.source:
             str_repr += f" {self.source}"
@@ -280,19 +301,24 @@ class Document(BaseMedia):
 
     @classmethod
     def is_lc_serializable(cls) -> bool:
-        """Return whether this class is serializable."""
+        """Return True as this class is serializable."""
         return True
 
     @classmethod
     def get_lc_namespace(cls) -> list[str]:
         """Get the namespace of the langchain object.
 
-        Default namespace is ["langchain", "schema", "document"].
+        Returns:
+            ["langchain", "schema", "document"]
         """
         return ["langchain", "schema", "document"]
 
     def __str__(self) -> str:
-        """Override __str__ to restrict it to page_content and metadata."""
+        """Override __str__ to restrict it to page_content and metadata.
+
+        Returns:
+            A string representation of the Document.
+        """
         # The format matches pydantic format for __str__.
         #
         # The purpose of this change is to make sure that user code that
diff --git a/libs/core/langchain_core/example_selectors/base.py b/libs/core/langchain_core/example_selectors/base.py
index e344e80551f..ec845cfc2e9 100644
--- a/libs/core/langchain_core/example_selectors/base.py
+++ b/libs/core/langchain_core/example_selectors/base.py
@@ -16,6 +16,9 @@ class BaseExampleSelector(ABC):
         Args:
             example: A dictionary with keys as input variables
                 and values as their values.
+
+        Returns:
+            Any return value.
         """
 
     async def aadd_example(self, example: dict[str, str]) -> Any:
@@ -24,6 +27,9 @@ class BaseExampleSelector(ABC):
         Args:
             example: A dictionary with keys as input variables
                 and values as their values.
+
+        Returns:
+            Any return value.
         """
         return await run_in_executor(None, self.add_example, example)
 
@@ -34,6 +40,9 @@ class BaseExampleSelector(ABC):
         Args:
             input_variables: A dictionary with keys as input variables
                 and values as their values.
+
+        Returns:
+            A list of examples.
         """
 
     async def aselect_examples(self, input_variables: dict[str, str]) -> list[dict]:
@@ -42,5 +51,8 @@ class BaseExampleSelector(ABC):
         Args:
             input_variables: A dictionary with keys as input variables
                 and values as their values.
+
+        Returns:
+            A list of examples.
         """
         return await run_in_executor(None, self.select_examples, input_variables)
diff --git a/libs/core/langchain_core/exceptions.py b/libs/core/langchain_core/exceptions.py
index cde6d6ff8ce..6aa8d89bc1f 100644
--- a/libs/core/langchain_core/exceptions.py
+++ b/libs/core/langchain_core/exceptions.py
@@ -42,6 +42,10 @@ class OutputParserException(ValueError, LangChainException):  # noqa: N818
                 previous output was improperly structured, in the hopes that it will
                 update the output to the correct format.
                 Defaults to False.
+
+        Raises:
+            ValueError: If ``send_to_llm`` is True but either observation or
+                ``llm_output`` are not provided.
         """
         if isinstance(error, str):
             error = create_message(
@@ -77,6 +81,9 @@ def create_message(*, message: str, error_code: ErrorCode) -> str:
     Args:
         message: The message to display.
         error_code: The error code to display.
+
+    Returns:
+        The full message with the troubleshooting link.
     """
     return (
         f"{message}\n"
diff --git a/libs/core/langchain_core/indexing/api.py b/libs/core/langchain_core/indexing/api.py
index bb232b298fe..7e938355fb1 100644
--- a/libs/core/langchain_core/indexing/api.py
+++ b/libs/core/langchain_core/indexing/api.py
@@ -185,6 +185,9 @@ def _get_document_with_hash(
             When changing the key encoder, you must change the
             index as well to avoid duplicated documents in the cache.
 
+    Raises:
+        ValueError: If the metadata cannot be serialized using json.
+
     Returns:
         Document with a unique identifier based on the hash of the content and metadata.
     """
@@ -374,6 +377,9 @@ def index(
         ValueError: If vectorstore does not have
             "delete" and "add_documents" required methods.
         ValueError: If source_id_key is not None, but is not a string or callable.
+        TypeError: If ``vectorstore`` is not a VectorStore or a DocumentIndex.
+        AssertionError: If ``source_id`` is None when cleanup mode is incremental.
+            (should be unreachable code).
 
     .. version_modified:: 0.3.25
 
@@ -708,6 +714,9 @@ async def aindex(
         ValueError: If vectorstore does not have
             "adelete" and "aadd_documents" required methods.
         ValueError: If source_id_key is not None, but is not a string or callable.
+        TypeError: If ``vector_store`` is not a VectorStore or DocumentIndex.
+        AssertionError: If ``source_id_key`` is None when cleanup mode is
+            incremental or ``scoped_full`` (should be unreachable).
 
     .. version_modified:: 0.3.25
 
diff --git a/libs/core/langchain_core/indexing/base.py b/libs/core/langchain_core/indexing/base.py
index 0de0b8cdee2..6e638ebd722 100644
--- a/libs/core/langchain_core/indexing/base.py
+++ b/libs/core/langchain_core/indexing/base.py
@@ -7,6 +7,8 @@ import time
 from abc import ABC, abstractmethod
 from typing import TYPE_CHECKING, Any, Optional, TypedDict
 
+from typing_extensions import override
+
 from langchain_core._api import beta
 from langchain_core.retrievers import BaseRetriever
 from langchain_core.runnables import run_in_executor
@@ -256,12 +258,12 @@ class InMemoryRecordManager(RecordManager):
     async def acreate_schema(self) -> None:
         """In-memory schema creation is simply ensuring the structure is initialized."""
 
+    @override
     def get_time(self) -> float:
-        """Get the current server time as a high resolution timestamp!"""
         return time.time()
 
+    @override
     async def aget_time(self) -> float:
-        """Async get the current server time as a high resolution timestamp!"""
         return self.get_time()
 
     def update(
@@ -322,11 +324,6 @@ class InMemoryRecordManager(RecordManager):
                 raise an error.
                 This is meant to help prevent time-drift issues since
                 time may not be monotonically increasing!
-
-        Raises:
-            ValueError: If the length of keys doesn't match the length of group
-                ids.
-            ValueError: If time_at_least is in the future.
         """
         self.update(keys, group_ids=group_ids, time_at_least=time_at_least)
 
diff --git a/libs/core/langchain_core/indexing/in_memory.py b/libs/core/langchain_core/indexing/in_memory.py
index 34609a0370d..02c11ffd198 100644
--- a/libs/core/langchain_core/indexing/in_memory.py
+++ b/libs/core/langchain_core/indexing/in_memory.py
@@ -32,7 +32,17 @@ class InMemoryDocumentIndex(DocumentIndex):
 
     @override
     def upsert(self, items: Sequence[Document], /, **kwargs: Any) -> UpsertResponse:
-        """Upsert items into the index."""
+        """Upsert documents into the index.
+
+        Args:
+            items: Sequence of documents to add to the index.
+            **kwargs: Additional keyword arguments.
+
+        Returns:
+            A response object that contains the list of IDs that were
+            successfully added or updated in the index and the list of IDs that
+            failed to be added or updated.
+        """
         ok_ids = []
 
         for item in items:
@@ -51,7 +61,18 @@ class InMemoryDocumentIndex(DocumentIndex):
 
     @override
     def delete(self, ids: Optional[list[str]] = None, **kwargs: Any) -> DeleteResponse:
-        """Delete by ID."""
+        """Delete by IDs.
+
+        Args:
+            ids: List of ids to delete.
+
+        Raises:
+            ValueError: If ids is None.
+
+        Returns:
+            A response object that contains the list of IDs that were successfully
+            deleted and the list of IDs that failed to be deleted.
+        """
         if ids is None:
             msg = "IDs must be provided for deletion"
             raise ValueError(msg)
@@ -69,7 +90,6 @@ class InMemoryDocumentIndex(DocumentIndex):
 
     @override
     def get(self, ids: Sequence[str], /, **kwargs: Any) -> list[Document]:
-        """Get by ids."""
         return [self.store[id_] for id_ in ids if id_ in self.store]
 
     @override
diff --git a/libs/core/langchain_core/language_models/base.py b/libs/core/langchain_core/language_models/base.py
index 9f9856d7c6c..80be6ff7305 100644
--- a/libs/core/langchain_core/language_models/base.py
+++ b/libs/core/langchain_core/language_models/base.py
@@ -59,6 +59,12 @@ def get_tokenizer() -> Any:
 
     This function is cached to avoid re-loading the tokenizer every time it is called.
 
+    Raises:
+        ImportError: If the transformers package is not installed.
+
+    Returns:
+        The GPT-2 tokenizer instance.
+
     """
     try:
         from transformers import GPT2TokenizerFast  # type: ignore[import-not-found]
diff --git a/libs/core/langchain_core/language_models/chat_models.py b/libs/core/langchain_core/language_models/chat_models.py
index 2ab0d6bb759..f4ec3d48af9 100644
--- a/libs/core/langchain_core/language_models/chat_models.py
+++ b/libs/core/langchain_core/language_models/chat_models.py
@@ -161,6 +161,9 @@ def generate_from_stream(stream: Iterator[ChatGenerationChunk]) -> ChatResult:
     Args:
         stream: Iterator of ``ChatGenerationChunk``.
 
+    Raises:
+        ValueError: If no generations are found in the stream.
+
     Returns:
         ChatResult: Chat result.
 
@@ -328,7 +331,7 @@ class BaseChatModel(BaseLanguageModel[BaseMessage], ABC):
     @model_validator(mode="before")
     @classmethod
     def raise_deprecation(cls, values: dict) -> Any:
-        """Raise deprecation warning if ``callback_manager`` is used.
+        """Emit deprecation warning if ``callback_manager`` is used.
 
         Args:
             values (Dict): Values to validate.
@@ -336,9 +339,6 @@ class BaseChatModel(BaseLanguageModel[BaseMessage], ABC):
         Returns:
             Dict: Validated values.
 
-        Raises:
-            DeprecationWarning: If ``callback_manager`` is used.
-
         """
         if values.get("callback_manager") is not None:
             warnings.warn(
@@ -1185,7 +1185,17 @@ class BaseChatModel(BaseLanguageModel[BaseMessage], ABC):
         run_manager: Optional[CallbackManagerForLLMRun] = None,
         **kwargs: Any,
     ) -> ChatResult:
-        """Top Level call."""
+        """Generate the result.
+
+        Args:
+            messages: The messages to generate from.
+            stop: Optional list of stop words to use when generating.
+            run_manager: Optional callback manager to use for this call.
+            **kwargs: Additional keyword arguments to pass to the model.
+
+        Returns:
+            The chat result.
+        """
 
     async def _agenerate(
         self,
@@ -1194,7 +1204,17 @@ class BaseChatModel(BaseLanguageModel[BaseMessage], ABC):
         run_manager: Optional[AsyncCallbackManagerForLLMRun] = None,
         **kwargs: Any,
     ) -> ChatResult:
-        """Top Level call."""
+        """Generate the result.
+
+        Args:
+            messages: The messages to generate from.
+            stop: Optional list of stop words to use when generating.
+            run_manager: Optional callback manager to use for this call.
+            **kwargs: Additional keyword arguments to pass to the model.
+
+        Returns:
+            The chat result.
+        """
         return await run_in_executor(
             None,
             self._generate,
@@ -1211,6 +1231,17 @@ class BaseChatModel(BaseLanguageModel[BaseMessage], ABC):
         run_manager: Optional[CallbackManagerForLLMRun] = None,
         **kwargs: Any,
     ) -> Iterator[ChatGenerationChunk]:
+        """Stream the output of the model.
+
+        Args:
+            messages: The messages to generate from.
+            stop: Optional list of stop words to use when generating.
+            run_manager: Optional callback manager to use for this call.
+            **kwargs: Additional keyword arguments to pass to the model.
+
+        Yields:
+            The chat generation chunks.
+        """
         raise NotImplementedError
 
     async def _astream(
@@ -1220,6 +1251,17 @@ class BaseChatModel(BaseLanguageModel[BaseMessage], ABC):
         run_manager: Optional[AsyncCallbackManagerForLLMRun] = None,
         **kwargs: Any,
     ) -> AsyncIterator[ChatGenerationChunk]:
+        """Stream the output of the model.
+
+        Args:
+            messages: The messages to generate from.
+            stop: Optional list of stop words to use when generating.
+            run_manager: Optional callback manager to use for this call.
+            **kwargs: Additional keyword arguments to pass to the model.
+
+        Yields:
+            The chat generation chunks.
+        """
         iterator = await run_in_executor(
             None,
             self._stream,
@@ -1259,6 +1301,9 @@ class BaseChatModel(BaseLanguageModel[BaseMessage], ABC):
             **kwargs: Arbitrary additional keyword arguments. These are usually passed
                 to the model provider API call.
 
+        Raises:
+            ValueError: If the generation is not a chat generation.
+
         Returns:
             The model output message.
 
@@ -1320,6 +1365,9 @@ class BaseChatModel(BaseLanguageModel[BaseMessage], ABC):
             **kwargs: Arbitrary additional keyword arguments. These are usually passed
                 to the model provider API call.
 
+        Raises:
+            ValueError: If the output is not a string.
+
         Returns:
             The predicted output string.
 
@@ -1434,6 +1482,11 @@ class BaseChatModel(BaseLanguageModel[BaseMessage], ABC):
                 will be caught and returned as well. The final output is always a dict
                 with keys ``'raw'``, ``'parsed'``, and ``'parsing_error'``.
 
+        Raises:
+            ValueError: If there are any unsupported ``kwargs``.
+            NotImplementedError: If the model does not implement
+                ``with_structured_output()``.
+
         Returns:
             A Runnable that takes same inputs as a :class:`langchain_core.language_models.chat.BaseChatModel`.
 
diff --git a/libs/core/langchain_core/language_models/fake_chat_models.py b/libs/core/langchain_core/language_models/fake_chat_models.py
index c6e78b5389a..3b90259e525 100644
--- a/libs/core/langchain_core/language_models/fake_chat_models.py
+++ b/libs/core/langchain_core/language_models/fake_chat_models.py
@@ -75,12 +75,13 @@ class FakeListChatModel(SimpleChatModel):
     @override
     def _call(
         self,
-        messages: list[BaseMessage],
-        stop: Optional[list[str]] = None,
-        run_manager: Optional[CallbackManagerForLLMRun] = None,
+        *args: Any,
         **kwargs: Any,
     ) -> str:
-        """First try to lookup in queries, else return 'foo' or 'bar'."""
+        """Return the next response in the list.
+
+        Cycle back to the start if at the end.
+        """
         if self.sleep is not None:
             time.sleep(self.sleep)
         response = self.responses[self.i]
@@ -239,7 +240,6 @@ class GenericFakeChatModel(BaseChatModel):
         run_manager: Optional[CallbackManagerForLLMRun] = None,
         **kwargs: Any,
     ) -> ChatResult:
-        """Top Level call."""
         message = next(self.messages)
         message_ = AIMessage(content=message) if isinstance(message, str) else message
         generation = ChatGeneration(message=message_)
@@ -252,7 +252,6 @@ class GenericFakeChatModel(BaseChatModel):
         run_manager: Optional[CallbackManagerForLLMRun] = None,
         **kwargs: Any,
     ) -> Iterator[ChatGenerationChunk]:
-        """Stream the output of the model."""
         chat_result = self._generate(
             messages, stop=stop, run_manager=run_manager, **kwargs
         )
@@ -362,7 +361,6 @@ class ParrotFakeChatModel(BaseChatModel):
         run_manager: Optional[CallbackManagerForLLMRun] = None,
         **kwargs: Any,
     ) -> ChatResult:
-        """Top Level call."""
         return ChatResult(generations=[ChatGeneration(message=messages[-1])])
 
     @property
diff --git a/libs/core/langchain_core/language_models/llms.py b/libs/core/langchain_core/language_models/llms.py
index 10a5f06121f..c274e02310d 100644
--- a/libs/core/langchain_core/language_models/llms.py
+++ b/libs/core/langchain_core/language_models/llms.py
@@ -664,7 +664,18 @@ class BaseLLM(BaseLanguageModel[str], ABC):
         run_manager: Optional[CallbackManagerForLLMRun] = None,
         **kwargs: Any,
     ) -> LLMResult:
-        """Run the LLM on the given prompts."""
+        """Run the LLM on the given prompts.
+
+        Args:
+            prompts: The prompts to generate from.
+            stop: Stop words to use when generating. Model output is cut off at the
+                first occurrence of any of the stop substrings.
+                If stop tokens are not supported consider raising NotImplementedError.
+            run_manager: Callback manager for the run.
+
+        Returns:
+            The LLM result.
+        """
 
     async def _agenerate(
         self,
@@ -673,7 +684,18 @@ class BaseLLM(BaseLanguageModel[str], ABC):
         run_manager: Optional[AsyncCallbackManagerForLLMRun] = None,
         **kwargs: Any,
     ) -> LLMResult:
-        """Run the LLM on the given prompts."""
+        """Run the LLM on the given prompts.
+
+        Args:
+            prompts: The prompts to generate from.
+            stop: Stop words to use when generating. Model output is cut off at the
+                first occurrence of any of the stop substrings.
+                If stop tokens are not supported consider raising NotImplementedError.
+            run_manager: Callback manager for the run.
+
+        Returns:
+            The LLM result.
+        """
         return await run_in_executor(
             None,
             self._generate,
@@ -706,8 +728,8 @@ class BaseLLM(BaseLanguageModel[str], ABC):
             **kwargs: Arbitrary additional keyword arguments. These are usually passed
                 to the model provider API call.
 
-        Returns:
-            An iterator of GenerationChunks.
+        Yields:
+            Generation chunks.
         """
         raise NotImplementedError
 
@@ -732,8 +754,8 @@ class BaseLLM(BaseLanguageModel[str], ABC):
             **kwargs: Arbitrary additional keyword arguments. These are usually passed
                 to the model provider API call.
 
-        Returns:
-            An async iterator of GenerationChunks.
+        Yields:
+            Generation chunks.
         """
         iterator = await run_in_executor(
             None,
@@ -854,6 +876,11 @@ class BaseLLM(BaseLanguageModel[str], ABC):
             **kwargs: Arbitrary additional keyword arguments. These are usually passed
                 to the model provider API call.
 
+        Raises:
+            ValueError: If prompts is not a list.
+            ValueError: If the length of ``callbacks``, ``tags``, ``metadata``, or
+                ``run_name`` (if provided) does not match the length of prompts.
+
         Returns:
             An LLMResult, which contains a list of candidate Generations for each input
                 prompt and additional model provider-specific output.
@@ -1114,6 +1141,10 @@ class BaseLLM(BaseLanguageModel[str], ABC):
             **kwargs: Arbitrary additional keyword arguments. These are usually passed
                 to the model provider API call.
 
+        Raises:
+            ValueError: If the length of ``callbacks``, ``tags``, ``metadata``, or
+                ``run_name`` (if provided) does not match the length of prompts.
+
         Returns:
             An LLMResult, which contains a list of candidate Generations for each input
                 prompt and additional model provider-specific output.
@@ -1389,7 +1420,7 @@ class BaseLLM(BaseLanguageModel[str], ABC):
         return AIMessage(content=content)
 
     def __str__(self) -> str:
-        """Get a string representation of the object for printing."""
+        """Return a string representation of the object for printing."""
         cls_name = f"\033[1m{self.__class__.__name__}\033[0m"
         return f"{cls_name}\nParams: {self._identifying_params}"
 
@@ -1537,7 +1568,6 @@ class LLM(BaseLLM):
         run_manager: Optional[CallbackManagerForLLMRun] = None,
         **kwargs: Any,
     ) -> LLMResult:
-        """Run the LLM on the given prompt and input."""
         # TODO: add caching here.
         generations = []
         new_arg_supported = inspect.signature(self._call).parameters.get("run_manager")
@@ -1557,7 +1587,6 @@ class LLM(BaseLLM):
         run_manager: Optional[AsyncCallbackManagerForLLMRun] = None,
         **kwargs: Any,
     ) -> LLMResult:
-        """Async run the LLM on the given prompt and input."""
         generations = []
         new_arg_supported = inspect.signature(self._acall).parameters.get("run_manager")
         for prompt in prompts:
diff --git a/libs/core/langchain_core/load/load.py b/libs/core/langchain_core/load/load.py
index 0c2cbf1f65e..52f4e2080b8 100644
--- a/libs/core/langchain_core/load/load.py
+++ b/libs/core/langchain_core/load/load.py
@@ -95,7 +95,21 @@ class Reviver:
         self.ignore_unserializable_fields = ignore_unserializable_fields
 
     def __call__(self, value: dict[str, Any]) -> Any:
-        """Revive the value."""
+        """Revive the value.
+
+        Args:
+            value: The value to revive.
+
+        Returns:
+            The revived value.
+
+        Raises:
+            ValueError: If the namespace is invalid.
+            ValueError: If trying to deserialize something that cannot
+                be deserialized in the current version of langchain-core.
+            NotImplementedError: If the object is not implemented and
+                ``ignore_unserializable_fields`` is False.
+        """
         if (
             value.get("lc") == 1
             and value.get("type") == "secret"
diff --git a/libs/core/langchain_core/load/serializable.py b/libs/core/langchain_core/load/serializable.py
index fde77e69932..b9d612be45c 100644
--- a/libs/core/langchain_core/load/serializable.py
+++ b/libs/core/langchain_core/load/serializable.py
@@ -79,9 +79,6 @@ def try_neq_default(value: Any, key: str, model: BaseModel) -> bool:
 
     Returns:
         Whether the value is different from the default.
-
-    Raises:
-        Exception: If the key is not in the model.
     """
     field = type(model).model_fields[key]
     return _try_neq_default(value, field)
@@ -148,6 +145,9 @@ class Serializable(BaseModel, ABC):
 
         For example, if the class is `langchain.llms.openai.OpenAI`, then the
         namespace is ["langchain", "llms", "openai"]
+
+        Returns:
+            The namespace as a list of strings.
         """
         return cls.__module__.split(".")
 
@@ -171,7 +171,7 @@ class Serializable(BaseModel, ABC):
 
     @classmethod
     def lc_id(cls) -> list[str]:
-        """A unique identifier for this class for serialization purposes.
+        """Return a unique identifier for this class for serialization purposes.
 
         The unique identifier is a list of strings that describes the path
         to the object.
@@ -203,6 +203,9 @@ class Serializable(BaseModel, ABC):
     def to_json(self) -> Union[SerializedConstructor, SerializedNotImplemented]:
         """Serialize the object to JSON.
 
+        Raises:
+            ValueError: If the class has deprecated attributes.
+
         Returns:
             A json serializable object or a SerializedNotImplemented object.
         """
@@ -276,7 +279,11 @@ class Serializable(BaseModel, ABC):
         }
 
     def to_json_not_implemented(self) -> SerializedNotImplemented:
-        """Serialize a "not implemented" object."""
+        """Serialize a "not implemented" object.
+
+        Returns:
+            SerializedNotImplemented.
+        """
         return to_json_not_implemented(self)
 
 
diff --git a/libs/core/langchain_core/messages/ai.py b/libs/core/langchain_core/messages/ai.py
index 86d48ec3254..e8640545649 100644
--- a/libs/core/langchain_core/messages/ai.py
+++ b/libs/core/langchain_core/messages/ai.py
@@ -310,14 +310,8 @@ class AIMessageChunk(AIMessage, BaseMessageChunk):
     def init_tool_calls(self) -> Self:
         """Initialize tool calls from tool call chunks.
 
-        Args:
-            values: The values to validate.
-
         Returns:
-            The values with tool calls initialized.
-
-        Raises:
-            ValueError: If the tool call chunks are malformed.
+            This ``AIMessageChunk``.
         """
         if not self.tool_call_chunks:
             if self.tool_calls:
@@ -392,7 +386,19 @@ class AIMessageChunk(AIMessage, BaseMessageChunk):
 def add_ai_message_chunks(
     left: AIMessageChunk, *others: AIMessageChunk
 ) -> AIMessageChunk:
-    """Add multiple AIMessageChunks together."""
+    """Add multiple ``AIMessageChunk``s together.
+
+    Args:
+        left: The first ``AIMessageChunk``.
+        *others: Other ``AIMessageChunk``s to add.
+
+    Raises:
+        ValueError: If the example values of the chunks are not the same.
+
+    Returns:
+        The resulting ``AIMessageChunk``.
+
+    """
     if any(left.example != o.example for o in others):
         msg = "Cannot concatenate AIMessageChunks with different example values."
         raise ValueError(msg)
@@ -491,6 +497,13 @@ def add_usage(
                 output_token_details=OutputTokenDetails(reasoning=4),
             )
 
+    Args:
+        left: The first ``UsageMetadata`` object.
+        right: The second ``UsageMetadata`` object.
+
+    Returns:
+        The sum of the two ``UsageMetadata`` objects.
+
     """
     if not (left or right):
         return UsageMetadata(input_tokens=0, output_tokens=0, total_tokens=0)
@@ -548,6 +561,13 @@ def subtract_usage(
                 output_token_details=OutputTokenDetails(reasoning=0),
             )
 
+    Args:
+        left: The first ``UsageMetadata`` object.
+        right: The second ``UsageMetadata`` object.
+
+    Returns:
+        The resulting ``UsageMetadata`` after subtraction.
+
     """
     if not (left or right):
         return UsageMetadata(input_tokens=0, output_tokens=0, total_tokens=0)
diff --git a/libs/core/langchain_core/messages/base.py b/libs/core/langchain_core/messages/base.py
index ba976286b75..2f831d79d02 100644
--- a/libs/core/langchain_core/messages/base.py
+++ b/libs/core/langchain_core/messages/base.py
@@ -84,7 +84,8 @@ class BaseMessage(Serializable):
     def get_lc_namespace(cls) -> list[str]:
         """Get the namespace of the langchain object.
 
-        Default is ["langchain", "schema", "messages"].
+        Returns:
+            ``["langchain", "schema", "messages"]``
         """
         return ["langchain", "schema", "messages"]
 
@@ -109,7 +110,14 @@ class BaseMessage(Serializable):
         )
 
     def __add__(self, other: Any) -> ChatPromptTemplate:
-        """Concatenate this message with another message."""
+        """Concatenate this message with another message.
+
+        Args:
+            other: Another message to concatenate with this one.
+
+        Returns:
+            A ChatPromptTemplate containing both messages.
+        """
         from langchain_core.prompts.chat import ChatPromptTemplate
 
         prompt = ChatPromptTemplate(messages=[self])
diff --git a/libs/core/langchain_core/messages/content_blocks.py b/libs/core/langchain_core/messages/content_blocks.py
index 83a66fb123a..e90426ebb13 100644
--- a/libs/core/langchain_core/messages/content_blocks.py
+++ b/libs/core/langchain_core/messages/content_blocks.py
@@ -88,7 +88,18 @@ def is_data_content_block(
 
 
 def convert_to_openai_image_block(content_block: dict[str, Any]) -> dict:
-    """Convert image content block to format expected by OpenAI Chat Completions API."""
+    """Convert image content block to format expected by OpenAI Chat Completions API.
+
+    Args:
+        content_block: The content block to convert.
+
+    Raises:
+        ValueError: If the source type is not supported or if ``mime_type`` is missing
+            for base64 data.
+
+    Returns:
+        A dictionary formatted for OpenAI's API.
+    """
     if content_block["source_type"] == "url":
         return {
             "type": "image_url",
@@ -112,7 +123,17 @@ def convert_to_openai_image_block(content_block: dict[str, Any]) -> dict:
 
 
 def convert_to_openai_data_block(block: dict) -> dict:
-    """Format standard data content block to format expected by OpenAI."""
+    """Format standard data content block to format expected by OpenAI.
+
+    Args:
+        block: A data content block.
+
+    Raises:
+        ValueError: If the block type or source type is not supported.
+
+    Returns:
+        A dictionary formatted for OpenAI's API.
+    """
     if block["type"] == "image":
         formatted_block = convert_to_openai_image_block(block)
 
diff --git a/libs/core/langchain_core/messages/tool.py b/libs/core/langchain_core/messages/tool.py
index 4d847c86d97..b2f858d8138 100644
--- a/libs/core/langchain_core/messages/tool.py
+++ b/libs/core/langchain_core/messages/tool.py
@@ -217,6 +217,9 @@ def tool_call(
         name: The name of the tool to be called.
         args: The arguments to the tool call.
         id: An identifier associated with the tool call.
+
+    Returns:
+        The created tool call.
     """
     return ToolCall(name=name, args=args, id=id, type="tool_call")
 
@@ -267,6 +270,9 @@ def tool_call_chunk(
         args: The arguments to the tool call.
         id: An identifier associated with the tool call.
         index: The index of the tool call in a sequence.
+
+    Returns:
+        The created tool call chunk.
     """
     return ToolCallChunk(
         name=name, args=args, id=id, index=index, type="tool_call_chunk"
@@ -305,6 +311,9 @@ def invalid_tool_call(
         args: The arguments to the tool call.
         id: An identifier associated with the tool call.
         error: An error message associated with the tool call.
+
+    Returns:
+        The created invalid tool call.
     """
     return InvalidToolCall(
         name=name, args=args, id=id, error=error, type="invalid_tool_call"
@@ -314,7 +323,14 @@ def invalid_tool_call(
 def default_tool_parser(
     raw_tool_calls: list[dict],
 ) -> tuple[list[ToolCall], list[InvalidToolCall]]:
-    """Best-effort parsing of tools."""
+    """Best-effort parsing of tools.
+
+    Args:
+        raw_tool_calls: List of raw tool call dicts to parse.
+
+    Returns:
+        A list of tool calls and invalid tool calls.
+    """
     tool_calls = []
     invalid_tool_calls = []
     for raw_tool_call in raw_tool_calls:
@@ -342,7 +358,14 @@ def default_tool_parser(
 
 
 def default_tool_chunk_parser(raw_tool_calls: list[dict]) -> list[ToolCallChunk]:
-    """Best-effort parsing of tool chunks."""
+    """Best-effort parsing of tool chunks.
+
+    Args:
+        raw_tool_calls: List of raw tool call dicts to parse.
+
+    Returns:
+        List of parsed ToolCallChunk objects.
+    """
     tool_call_chunks = []
     for tool_call in raw_tool_calls:
         if "function" not in tool_call:
diff --git a/libs/core/langchain_core/messages/utils.py b/libs/core/langchain_core/messages/utils.py
index 16285eaefb2..c63f5b1c421 100644
--- a/libs/core/langchain_core/messages/utils.py
+++ b/libs/core/langchain_core/messages/utils.py
@@ -1046,6 +1046,10 @@ def convert_to_openai_messages(
                     with a single content block of type 'text'. If a message has content
                     blocks these are left as is.
 
+    Raises:
+        ValueError: if an unrecognized ``text_format`` is specified, or if a message
+            content block is missing expected keys.
+
     Returns:
         The return type depends on the input type:
             - dict:
diff --git a/libs/core/langchain_core/output_parsers/list.py b/libs/core/langchain_core/output_parsers/list.py
index d60afe3554d..cc8ca4238cb 100644
--- a/libs/core/langchain_core/output_parsers/list.py
+++ b/libs/core/langchain_core/output_parsers/list.py
@@ -143,10 +143,7 @@ class CommaSeparatedListOutputParser(ListOutputParser):
 
     @classmethod
     def is_lc_serializable(cls) -> bool:
-        """Check if the langchain object is serializable.
-
-        Returns True.
-        """
+        """Return True as this class is serializable."""
         return True
 
     @classmethod
@@ -154,8 +151,7 @@ class CommaSeparatedListOutputParser(ListOutputParser):
         """Get the namespace of the langchain object.
 
         Returns:
-            A list of strings.
-            Default is ["langchain", "output_parsers", "list"].
+            ``["langchain", "output_parsers", "list"]``
         """
         return ["langchain", "output_parsers", "list"]
 
@@ -213,15 +209,8 @@ class NumberedListOutputParser(ListOutputParser):
         """
         return re.findall(self.pattern, text)
 
+    @override
     def parse_iter(self, text: str) -> Iterator[re.Match]:
-        """Parse the output of an LLM call.
-
-        Args:
-            text: The output of an LLM call.
-
-        Yields:
-            A match object for each part of the output.
-        """
         return re.finditer(self.pattern, text)
 
     @property
@@ -250,15 +239,8 @@ class MarkdownListOutputParser(ListOutputParser):
         """
         return re.findall(self.pattern, text, re.MULTILINE)
 
+    @override
     def parse_iter(self, text: str) -> Iterator[re.Match]:
-        """Parse the output of an LLM call.
-
-        Args:
-            text: The output of an LLM call.
-
-        Yields:
-            A match object for each part of the output.
-        """
         return re.finditer(self.pattern, text, re.MULTILINE)
 
     @property
diff --git a/libs/core/langchain_core/output_parsers/openai_functions.py b/libs/core/langchain_core/output_parsers/openai_functions.py
index 129c9855061..5518f36a78e 100644
--- a/libs/core/langchain_core/output_parsers/openai_functions.py
+++ b/libs/core/langchain_core/output_parsers/openai_functions.py
@@ -261,6 +261,9 @@ class PydanticOutputFunctionsParser(OutputFunctionsParser):
             result: The result of the LLM call.
             partial: Whether to parse partial JSON objects. Default is False.
 
+        Raises:
+            ValueError: If the pydantic schema is not valid.
+
         Returns:
             The parsed JSON object.
         """
diff --git a/libs/core/langchain_core/output_parsers/openai_tools.py b/libs/core/langchain_core/output_parsers/openai_tools.py
index 5c2e0cd6644..44563e9a3c2 100644
--- a/libs/core/langchain_core/output_parsers/openai_tools.py
+++ b/libs/core/langchain_core/output_parsers/openai_tools.py
@@ -231,6 +231,9 @@ class JsonOutputKeyToolsParser(JsonOutputToolsParser):
                 If False, the output will be the full JSON object.
                 Default is False.
 
+        Raises:
+            OutputParserException: If the generation is not a chat generation.
+
         Returns:
             The parsed tool calls.
         """
@@ -316,7 +319,9 @@ class PydanticToolsParser(JsonOutputToolsParser):
             The parsed Pydantic objects.
 
         Raises:
-            OutputParserException: If the output is not valid JSON.
+            ValueError: If the tool call arguments are not a dict.
+            ValidationError: If the tool call arguments do not conform
+                to the Pydantic model.
         """
         json_results = super().parse_result(result, partial=partial)
         if not json_results:
diff --git a/libs/core/langchain_core/output_parsers/pydantic.py b/libs/core/langchain_core/output_parsers/pydantic.py
index b543df55768..1785cbc60fa 100644
--- a/libs/core/langchain_core/output_parsers/pydantic.py
+++ b/libs/core/langchain_core/output_parsers/pydantic.py
@@ -54,6 +54,10 @@ class PydanticOutputParser(JsonOutputParser, Generic[TBaseModel]):
                 all the keys that have been returned so far.
                 Defaults to False.
 
+        Raises:
+            OutputParserException: If the result is not valid JSON
+                or does not conform to the pydantic model.
+
         Returns:
             The parsed pydantic object.
         """
diff --git a/libs/core/langchain_core/output_parsers/string.py b/libs/core/langchain_core/output_parsers/string.py
index 4f952c68892..c2194e8bddf 100644
--- a/libs/core/langchain_core/output_parsers/string.py
+++ b/libs/core/langchain_core/output_parsers/string.py
@@ -19,7 +19,8 @@ class StrOutputParser(BaseTransformOutputParser[str]):
     def get_lc_namespace(cls) -> list[str]:
         """Get the namespace of the langchain object.
 
-        Default is ["langchain", "schema", "output_parser"].
+        Returns:
+            ``["langchain", "schema", "output_parser"]``
         """
         return ["langchain", "schema", "output_parser"]
 
diff --git a/libs/core/langchain_core/output_parsers/xml.py b/libs/core/langchain_core/output_parsers/xml.py
index 483d9871c1a..fcbd68a89d0 100644
--- a/libs/core/langchain_core/output_parsers/xml.py
+++ b/libs/core/langchain_core/output_parsers/xml.py
@@ -136,9 +136,6 @@ class _StreamingParser:
         """Close the parser.
 
         This should be called after all chunks have been parsed.
-
-        Raises:
-            xml.etree.ElementTree.ParseError: If the XML is not well-formed.
         """
         # Ignore ParseError. This will ignore any incomplete XML at the end of the input
         with contextlib.suppress(xml.etree.ElementTree.ParseError):
diff --git a/libs/core/langchain_core/outputs/chat_generation.py b/libs/core/langchain_core/outputs/chat_generation.py
index d42f2038d34..594066f2fb7 100644
--- a/libs/core/langchain_core/outputs/chat_generation.py
+++ b/libs/core/langchain_core/outputs/chat_generation.py
@@ -47,9 +47,6 @@ class ChatGeneration(Generation):
 
         Returns:
             The values of the object with the text attribute set.
-
-        Raises:
-            ValueError: If the message is not a string or a list.
         """
         text = ""
         if isinstance(self.message.content, str):
@@ -83,11 +80,18 @@ class ChatGenerationChunk(ChatGeneration):
     def __add__(
         self, other: Union[ChatGenerationChunk, list[ChatGenerationChunk]]
     ) -> ChatGenerationChunk:
-        """Concatenate two ChatGenerationChunks.
+        """Concatenate two ``ChatGenerationChunk``s.
 
         Args:
-            other: The other ChatGenerationChunk or list of ChatGenerationChunks to
-                concatenate.
+            other: The other ``ChatGenerationChunk`` or list of ``ChatGenerationChunk``
+                to concatenate.
+
+        Raises:
+            TypeError: If other is not a ``ChatGenerationChunk`` or list of
+                ``ChatGenerationChunk``.
+
+        Returns:
+            A new ``ChatGenerationChunk`` concatenated from self and other.
         """
         if isinstance(other, ChatGenerationChunk):
             generation_info = merge_dicts(
@@ -116,7 +120,14 @@ class ChatGenerationChunk(ChatGeneration):
 def merge_chat_generation_chunks(
     chunks: list[ChatGenerationChunk],
 ) -> Union[ChatGenerationChunk, None]:
-    """Merge a list of ChatGenerationChunks into a single ChatGenerationChunk."""
+    """Merge a list of ``ChatGenerationChunk``s into a single ``ChatGenerationChunk``.
+
+    Args:
+        chunks: A list of ``ChatGenerationChunk`` to merge.
+
+    Returns:
+        A merged ``ChatGenerationChunk``, or None if the input list is empty.
+    """
     if not chunks:
         return None
 
diff --git a/libs/core/langchain_core/outputs/generation.py b/libs/core/langchain_core/outputs/generation.py
index 1167616d6bc..cd06c20e673 100644
--- a/libs/core/langchain_core/outputs/generation.py
+++ b/libs/core/langchain_core/outputs/generation.py
@@ -39,14 +39,15 @@ class Generation(Serializable):
 
     @classmethod
     def is_lc_serializable(cls) -> bool:
-        """Return whether this class is serializable."""
+        """Return True as this class is serializable."""
         return True
 
     @classmethod
     def get_lc_namespace(cls) -> list[str]:
         """Get the namespace of the langchain object.
 
-        Default namespace is ["langchain", "schema", "output"].
+        Returns:
+            ``["langchain", "schema", "output"]``
         """
         return ["langchain", "schema", "output"]
 
@@ -55,7 +56,17 @@ class GenerationChunk(Generation):
     """Generation chunk, which can be concatenated with other Generation chunks."""
 
     def __add__(self, other: GenerationChunk) -> GenerationChunk:
-        """Concatenate two GenerationChunks."""
+        """Concatenate two ``GenerationChunk``s.
+
+        Args:
+            other: Another ``GenerationChunk`` to concatenate with.
+
+        Raises:
+            TypeError: If other is not a ``GenerationChunk``.
+
+        Returns:
+            A new ``GenerationChunk`` concatenated from self and other.
+        """
         if isinstance(other, GenerationChunk):
             generation_info = merge_dicts(
                 self.generation_info or {},
diff --git a/libs/core/langchain_core/outputs/llm_result.py b/libs/core/langchain_core/outputs/llm_result.py
index 08e5e78f2a7..088b909755c 100644
--- a/libs/core/langchain_core/outputs/llm_result.py
+++ b/libs/core/langchain_core/outputs/llm_result.py
@@ -91,7 +91,14 @@ class LLMResult(BaseModel):
         return llm_results
 
     def __eq__(self, other: object) -> bool:
-        """Check for LLMResult equality by ignoring any metadata related to runs."""
+        """Check for ``LLMResult`` equality by ignoring any metadata related to runs.
+
+        Args:
+            other: Another ``LLMResult`` object to compare against.
+
+        Returns:
+            True if the generations and ``llm_output`` are equal, False otherwise.
+        """
         if not isinstance(other, LLMResult):
             return NotImplemented
         return (
diff --git a/libs/core/langchain_core/prompt_values.py b/libs/core/langchain_core/prompt_values.py
index 7652bd76e3c..5b7c2e414bb 100644
--- a/libs/core/langchain_core/prompt_values.py
+++ b/libs/core/langchain_core/prompt_values.py
@@ -30,7 +30,7 @@ class PromptValue(Serializable, ABC):
 
     @classmethod
     def is_lc_serializable(cls) -> bool:
-        """Return whether this class is serializable. Defaults to True."""
+        """Return True as this class is serializable."""
         return True
 
     @classmethod
@@ -38,7 +38,9 @@ class PromptValue(Serializable, ABC):
         """Get the namespace of the langchain object.
 
         This is used to determine the namespace of the object when serializing.
-        Defaults to ["langchain", "schema", "prompt"].
+
+        Returns:
+            ``["langchain", "schema", "prompt"]``
         """
         return ["langchain", "schema", "prompt"]
 
@@ -63,7 +65,9 @@ class StringPromptValue(PromptValue):
         """Get the namespace of the langchain object.
 
         This is used to determine the namespace of the object when serializing.
-        Defaults to ["langchain", "prompts", "base"].
+
+        Returns:
+            ``["langchain", "prompts", "base"]``
         """
         return ["langchain", "prompts", "base"]
 
@@ -98,7 +102,9 @@ class ChatPromptValue(PromptValue):
         """Get the namespace of the langchain object.
 
         This is used to determine the namespace of the object when serializing.
-        Defaults to ["langchain", "prompts", "chat"].
+
+        Returns:
+            ``["langchain", "prompts", "chat"]``
         """
         return ["langchain", "prompts", "chat"]
 
diff --git a/libs/core/langchain_core/prompts/base.py b/libs/core/langchain_core/prompts/base.py
index f36c69be8e6..6581c56902c 100644
--- a/libs/core/langchain_core/prompts/base.py
+++ b/libs/core/langchain_core/prompts/base.py
@@ -101,16 +101,14 @@ class BasePromptTemplate(
     def get_lc_namespace(cls) -> list[str]:
         """Get the namespace of the langchain object.
 
-        Returns ["langchain", "schema", "prompt_template"].
+        Returns:
+            ``["langchain", "schema", "prompt_template"]``
         """
         return ["langchain", "schema", "prompt_template"]
 
     @classmethod
     def is_lc_serializable(cls) -> bool:
-        """Return whether this class is serializable.
-
-        Returns True.
-        """
+        """Return True as this class is serializable."""
         return True
 
     model_config = ConfigDict(
@@ -341,9 +339,6 @@ class BasePromptTemplate(
 
         Returns:
             Dict: Dictionary representation of the prompt.
-
-        Raises:
-            NotImplementedError: If the prompt type is not implemented.
         """
         prompt_dict = super().model_dump(**kwargs)
         with contextlib.suppress(NotImplementedError):
diff --git a/libs/core/langchain_core/prompts/chat.py b/libs/core/langchain_core/prompts/chat.py
index 12728ef76e8..93bcb29730a 100644
--- a/libs/core/langchain_core/prompts/chat.py
+++ b/libs/core/langchain_core/prompts/chat.py
@@ -740,10 +740,18 @@ class BaseChatPromptTemplate(BasePromptTemplate, ABC):
 
     @abstractmethod
     def format_messages(self, **kwargs: Any) -> list[BaseMessage]:
-        """Format kwargs into a list of messages."""
+        """Format kwargs into a list of messages.
+
+        Returns:
+            List of messages.
+        """
 
     async def aformat_messages(self, **kwargs: Any) -> list[BaseMessage]:
-        """Async format kwargs into a list of messages."""
+        """Async format kwargs into a list of messages.
+
+        Returns:
+            List of messages.
+        """
         return self.format_messages(**kwargs)
 
     def pretty_repr(
@@ -925,9 +933,6 @@ class ChatPromptTemplate(BaseChatPromptTemplate):
             input_types: A dictionary of the types of the variables the prompt template
                 expects. If not provided, all variables are assumed to be strings.
 
-        Returns:
-            A chat prompt template.
-
         Examples:
             Instantiation from a list of message templates:
 
@@ -981,7 +986,11 @@ class ChatPromptTemplate(BaseChatPromptTemplate):
 
     @classmethod
     def get_lc_namespace(cls) -> list[str]:
-        """Get the namespace of the langchain object."""
+        """Get the namespace of the langchain object.
+
+        Returns:
+            ``["langchain", "prompts", "chat"]``
+        """
         return ["langchain", "prompts", "chat"]
 
     def __add__(self, other: Any) -> ChatPromptTemplate:
@@ -1185,6 +1194,9 @@ class ChatPromptTemplate(BaseChatPromptTemplate):
             **kwargs: keyword arguments to use for filling in template variables
                       in all the template messages in this chat template.
 
+        Raises:
+            ValueError: if messages are of unexpected types.
+
         Returns:
             list of formatted messages.
         """
@@ -1295,7 +1307,13 @@ class ChatPromptTemplate(BaseChatPromptTemplate):
     def __getitem__(
         self, index: Union[int, slice]
     ) -> Union[MessageLike, ChatPromptTemplate]:
-        """Use to index into the chat template."""
+        """Use to index into the chat template.
+
+        Returns:
+            If index is an int, returns the message at that index.
+            If index is a slice, returns a new ``ChatPromptTemplate``
+            containing the messages in that slice.
+        """
         if isinstance(index, slice):
             start, stop, step = index.indices(len(self.messages))
             messages = self.messages[start:stop:step]
@@ -1303,7 +1321,7 @@ class ChatPromptTemplate(BaseChatPromptTemplate):
         return self.messages[index]
 
     def __len__(self) -> int:
-        """Get the length of the chat template."""
+        """Return the length of the chat template."""
         return len(self.messages)
 
     @property
diff --git a/libs/core/langchain_core/prompts/dict.py b/libs/core/langchain_core/prompts/dict.py
index 0b5ee5072a2..135f8021b9d 100644
--- a/libs/core/langchain_core/prompts/dict.py
+++ b/libs/core/langchain_core/prompts/dict.py
@@ -31,18 +31,25 @@ class DictPromptTemplate(RunnableSerializable[dict, dict]):
         return _get_input_variables(self.template, self.template_format)
 
     def format(self, **kwargs: Any) -> dict[str, Any]:
-        """Format the prompt with the inputs."""
+        """Format the prompt with the inputs.
+
+        Returns:
+            A formatted dict.
+        """
         return _insert_input_variables(self.template, kwargs, self.template_format)
 
     async def aformat(self, **kwargs: Any) -> dict[str, Any]:
-        """Format the prompt with the inputs."""
+        """Format the prompt with the inputs.
+
+        Returns:
+            A formatted dict.
+        """
         return self.format(**kwargs)
 
     @override
     def invoke(
         self, input: dict, config: Optional[RunnableConfig] = None, **kwargs: Any
     ) -> dict:
-        """Invoke the prompt."""
         return self._call_with_config(
             lambda x: self.format(**x),
             input,
@@ -62,15 +69,16 @@ class DictPromptTemplate(RunnableSerializable[dict, dict]):
 
     @classmethod
     def is_lc_serializable(cls) -> bool:
-        """Return whether or not the class is serializable.
-
-        Returns: True.
-        """
+        """Return True as this class is serializable."""
         return True
 
     @classmethod
     def get_lc_namespace(cls) -> list[str]:
-        """Serialization namespace."""
+        """Get the namespace of the langchain object.
+
+        Returns:
+            ``["langchain_core", "prompts", "dict"]``
+        """
         return ["langchain_core", "prompts", "dict"]
 
     def pretty_repr(self, *, html: bool = False) -> str:
diff --git a/libs/core/langchain_core/prompts/few_shot.py b/libs/core/langchain_core/prompts/few_shot.py
index ddb09c2e320..70c95038208 100644
--- a/libs/core/langchain_core/prompts/few_shot.py
+++ b/libs/core/langchain_core/prompts/few_shot.py
@@ -117,7 +117,7 @@ class FewShotPromptTemplate(_FewShotPromptTemplateMixin, StringPromptTemplate):
 
     @classmethod
     def is_lc_serializable(cls) -> bool:
-        """Return whether or not the class is serializable."""
+        """Return False as this class is not serializable."""
         return False
 
     validate_template: bool = False
@@ -367,7 +367,7 @@ class FewShotChatMessagePromptTemplate(
 
     @classmethod
     def is_lc_serializable(cls) -> bool:
-        """Return whether or not the class is serializable."""
+        """Return False as this class is not serializable."""
         return False
 
     model_config = ConfigDict(
diff --git a/libs/core/langchain_core/prompts/few_shot_with_templates.py b/libs/core/langchain_core/prompts/few_shot_with_templates.py
index eaf8ab0fd15..5f3ad91fe48 100644
--- a/libs/core/langchain_core/prompts/few_shot_with_templates.py
+++ b/libs/core/langchain_core/prompts/few_shot_with_templates.py
@@ -46,7 +46,11 @@ class FewShotPromptWithTemplates(StringPromptTemplate):
 
     @classmethod
     def get_lc_namespace(cls) -> list[str]:
-        """Get the namespace of the langchain object."""
+        """Get the namespace of the langchain object.
+
+        Returns:
+            ``["langchain", "prompts", "few_shot_with_templates"]``
+        """
         return ["langchain", "prompts", "few_shot_with_templates"]
 
     @model_validator(mode="before")
diff --git a/libs/core/langchain_core/prompts/image.py b/libs/core/langchain_core/prompts/image.py
index 4240b6bdec0..95776dbba00 100644
--- a/libs/core/langchain_core/prompts/image.py
+++ b/libs/core/langchain_core/prompts/image.py
@@ -23,7 +23,12 @@ class ImagePromptTemplate(BasePromptTemplate[ImageURL]):
     Options are: 'f-string', 'mustache', 'jinja2'."""
 
     def __init__(self, **kwargs: Any) -> None:
-        """Create an image prompt template."""
+        """Create an image prompt template.
+
+        Raises:
+            ValueError: If the input variables contain ``'url'``, ``'path'``, or
+                ``'detail'``.
+        """
         if "input_variables" not in kwargs:
             kwargs["input_variables"] = []
 
@@ -44,7 +49,11 @@ class ImagePromptTemplate(BasePromptTemplate[ImageURL]):
 
     @classmethod
     def get_lc_namespace(cls) -> list[str]:
-        """Get the namespace of the langchain object."""
+        """Get the namespace of the langchain object.
+
+        Returns:
+            ``["langchain", "prompts", "image"]``
+        """
         return ["langchain", "prompts", "image"]
 
     def format_prompt(self, **kwargs: Any) -> PromptValue:
@@ -84,6 +93,7 @@ class ImagePromptTemplate(BasePromptTemplate[ImageURL]):
         Raises:
             ValueError: If the url is not provided.
             ValueError: If the url is not a string.
+            ValueError: If ``'path'`` is provided in the template or kwargs.
 
         Example:
 
@@ -128,9 +138,6 @@ class ImagePromptTemplate(BasePromptTemplate[ImageURL]):
 
         Returns:
             A formatted string.
-
-        Raises:
-            ValueError: If the path or url is not a string.
         """
         return await run_in_executor(None, self.format, **kwargs)
 
diff --git a/libs/core/langchain_core/prompts/message.py b/libs/core/langchain_core/prompts/message.py
index 668374a19f0..409f54320b1 100644
--- a/libs/core/langchain_core/prompts/message.py
+++ b/libs/core/langchain_core/prompts/message.py
@@ -18,17 +18,15 @@ class BaseMessagePromptTemplate(Serializable, ABC):
 
     @classmethod
     def is_lc_serializable(cls) -> bool:
-        """Return whether or not the class is serializable.
-
-        Returns: True.
-        """
+        """Return True as this class is serializable."""
         return True
 
     @classmethod
     def get_lc_namespace(cls) -> list[str]:
         """Get the namespace of the langchain object.
 
-        Default namespace is ["langchain", "prompts", "chat"].
+        Returns:
+            ``["langchain", "prompts", "chat"]``
         """
         return ["langchain", "prompts", "chat"]
 
diff --git a/libs/core/langchain_core/prompts/pipeline.py b/libs/core/langchain_core/prompts/pipeline.py
index bb11fda48fd..ee4ea4b0dca 100644
--- a/libs/core/langchain_core/prompts/pipeline.py
+++ b/libs/core/langchain_core/prompts/pipeline.py
@@ -55,7 +55,11 @@ class PipelinePromptTemplate(BasePromptTemplate):
 
     @classmethod
     def get_lc_namespace(cls) -> list[str]:
-        """Get the namespace of the langchain object."""
+        """Get the namespace of the langchain object.
+
+        Returns:
+            ``["langchain", "prompts", "pipeline"]``
+        """
         return ["langchain", "prompts", "pipeline"]
 
     @model_validator(mode="before")
diff --git a/libs/core/langchain_core/prompts/prompt.py b/libs/core/langchain_core/prompts/prompt.py
index 0066445a050..11a9922f92b 100644
--- a/libs/core/langchain_core/prompts/prompt.py
+++ b/libs/core/langchain_core/prompts/prompt.py
@@ -69,6 +69,11 @@ class PromptTemplate(StringPromptTemplate):
     @classmethod
     @override
     def get_lc_namespace(cls) -> list[str]:
+        """Get the namespace of the langchain object.
+
+        Returns:
+            ``["langchain", "prompts", "prompt"]``
+        """
         return ["langchain", "prompts", "prompt"]
 
     template: str
@@ -135,7 +140,16 @@ class PromptTemplate(StringPromptTemplate):
         return mustache_schema(self.template)
 
     def __add__(self, other: Any) -> PromptTemplate:
-        """Override the + operator to allow for combining prompt templates."""
+        """Override the + operator to allow for combining prompt templates.
+
+        Raises:
+            ValueError: If the template formats are not f-string or if there are
+                conflicting partial variables.
+            NotImplementedError: If the other object is not a ``PromptTemplate`` or str.
+
+        Returns:
+            A new ``PromptTemplate`` that is the combination of the two.
+        """
         # Allow for easy combining
         if isinstance(other, PromptTemplate):
             if self.template_format != "f-string":
diff --git a/libs/core/langchain_core/prompts/string.py b/libs/core/langchain_core/prompts/string.py
index 69b3fd64c82..12357bf3a27 100644
--- a/libs/core/langchain_core/prompts/string.py
+++ b/libs/core/langchain_core/prompts/string.py
@@ -268,7 +268,11 @@ class StringPromptTemplate(BasePromptTemplate, ABC):
 
     @classmethod
     def get_lc_namespace(cls) -> list[str]:
-        """Get the namespace of the langchain object."""
+        """Get the namespace of the langchain object.
+
+        Returns:
+            ``["langchain", "prompts", "base"]``
+        """
         return ["langchain", "prompts", "base"]
 
     def format_prompt(self, **kwargs: Any) -> PromptValue:
diff --git a/libs/core/langchain_core/prompts/structured.py b/libs/core/langchain_core/prompts/structured.py
index d05ace21ccf..0d2c5d90b0f 100644
--- a/libs/core/langchain_core/prompts/structured.py
+++ b/libs/core/langchain_core/prompts/structured.py
@@ -68,8 +68,11 @@ class StructuredPrompt(ChatPromptTemplate):
     def get_lc_namespace(cls) -> list[str]:
         """Get the namespace of the langchain object.
 
-        For example, if the class is `langchain.llms.openai.OpenAI`, then the
-        namespace is ["langchain", "llms", "openai"]
+        For example, if the class is ``langchain.llms.openai.OpenAI``, then the
+        namespace is ``["langchain", "llms", "openai"]``
+
+        Returns:
+            The namespace of the langchain object.
         """
         return cls.__module__.split(".")
 
diff --git a/libs/core/langchain_core/retrievers.py b/libs/core/langchain_core/retrievers.py
index 2a7cb681ff8..8e1acf56c16 100644
--- a/libs/core/langchain_core/retrievers.py
+++ b/libs/core/langchain_core/retrievers.py
@@ -362,6 +362,7 @@ class BaseRetriever(RunnableSerializable[RetrieverInput, RetrieverOutput], ABC):
         Args:
             query: String to find relevant documents for
             run_manager: The callback handler to use
+
         Returns:
             List of relevant documents
         """
diff --git a/libs/core/langchain_core/runnables/base.py b/libs/core/langchain_core/runnables/base.py
index c065cc7afbf..1f90b2f608c 100644
--- a/libs/core/langchain_core/runnables/base.py
+++ b/libs/core/langchain_core/runnables/base.py
@@ -245,7 +245,15 @@ class Runnable(ABC, Generic[Input, Output]):
     def get_name(
         self, suffix: Optional[str] = None, *, name: Optional[str] = None
     ) -> str:
-        """Get the name of the ``Runnable``."""
+        """Get the name of the ``Runnable``.
+
+        Args:
+            suffix: An optional suffix to append to the name.
+            name: An optional name to use instead of the ``Runnable``'s name.
+
+        Returns:
+            The name of the ``Runnable``.
+        """
         if name:
             name_ = name
         elif hasattr(self, "name") and self.name:
@@ -276,7 +284,13 @@ class Runnable(ABC, Generic[Input, Output]):
 
     @property
     def InputType(self) -> type[Input]:  # noqa: N802
-        """The type of input this ``Runnable`` accepts specified as a type annotation."""  # noqa: E501
+        """Input type.
+
+        The type of input this ``Runnable`` accepts specified as a type annotation.
+
+        Raises:
+            TypeError: If the input type cannot be inferred.
+        """
         # First loop through all parent classes and if any of them is
         # a pydantic model, we will pick up the generic parameterization
         # from that model via the __pydantic_generic_metadata__ attribute.
@@ -302,7 +316,13 @@ class Runnable(ABC, Generic[Input, Output]):
 
     @property
     def OutputType(self) -> type[Output]:  # noqa: N802
-        """The type of output this ``Runnable`` produces specified as a type annotation."""  # noqa: E501
+        """Output Type.
+
+        The type of output this ``Runnable`` produces specified as a type annotation.
+
+        Raises:
+            TypeError: If the output type cannot be inferred.
+        """
         # First loop through bases -- this will help generic
         # any pydantic models.
         for base in self.__class__.mro():
@@ -583,7 +603,17 @@ class Runnable(ABC, Generic[Input, Output]):
             Mapping[str, Union[Runnable[Any, Other], Callable[[Any], Other], Any]],
         ],
     ) -> RunnableSerializable[Input, Other]:
-        """Compose this ``Runnable`` with another object to create a ``RunnableSequence``."""  # noqa: E501
+        """Runnable "or" operator.
+
+        Compose this ``Runnable`` with another object to create a
+        ``RunnableSequence``.
+
+        Args:
+            other: Another ``Runnable`` or a ``Runnable``-like object.
+
+        Returns:
+            A new ``Runnable``.
+        """
         return RunnableSequence(self, coerce_to_runnable(other))
 
     def __ror__(
@@ -596,7 +626,17 @@ class Runnable(ABC, Generic[Input, Output]):
             Mapping[str, Union[Runnable[Other, Any], Callable[[Other], Any], Any]],
         ],
     ) -> RunnableSerializable[Other, Output]:
-        """Compose this ``Runnable`` with another object to create a ``RunnableSequence``."""  # noqa: E501
+        """Runnable "reverse-or" operator.
+
+        Compose this ``Runnable`` with another object to create a
+        ``RunnableSequence``.
+
+        Args:
+            other: Another ``Runnable`` or a ``Runnable``-like object.
+
+        Returns:
+            A new ``Runnable``.
+        """
         return RunnableSequence(coerce_to_runnable(other), self)
 
     def pipe(
@@ -604,11 +644,15 @@ class Runnable(ABC, Generic[Input, Output]):
         *others: Union[Runnable[Any, Other], Callable[[Any], Other]],
         name: Optional[str] = None,
     ) -> RunnableSerializable[Input, Other]:
-        """Compose this ``Runnable`` with ``Runnable``-like objects to make a ``RunnableSequence``.
+        """Pipe runnables.
+
+        Compose this ``Runnable`` with ``Runnable``-like objects to make a
+        ``RunnableSequence``.
 
         Equivalent to ``RunnableSequence(self, *others)`` or ``self | others[0] | ...``
 
         Example:
+
             .. code-block:: python
 
                 from langchain_core.runnables import RunnableLambda
@@ -636,13 +680,20 @@ class Runnable(ABC, Generic[Input, Output]):
                 await sequence.abatch([1, 2, 3])
                 # -> [4, 6, 8]
 
-        """  # noqa: E501
+        Args:
+            *others: Other ``Runnable`` or ``Runnable``-like objects to compose
+            name: An optional name for the resulting ``RunnableSequence``.
+
+        Returns:
+            A new ``Runnable``.
+        """
         return RunnableSequence(self, *others, name=name)
 
     def pick(self, keys: Union[str, list[str]]) -> RunnableSerializable[Any, Any]:
         """Pick keys from the output dict of this ``Runnable``.
 
         Pick single key:
+
             .. code-block:: python
 
                 import json
@@ -661,6 +712,7 @@ class Runnable(ABC, Generic[Input, Output]):
                 # -> [1, 2, 3]
 
         Pick list of keys:
+
             .. code-block:: python
 
                 from typing import Any
@@ -688,6 +740,12 @@ class Runnable(ABC, Generic[Input, Output]):
                 json_and_bytes_chain.invoke("[1, 2, 3]")
                 # -> {"json": [1, 2, 3], "bytes": b"[1, 2, 3]"}
 
+        Args:
+            keys: A key or list of keys to pick from the output dict.
+
+        Returns:
+            a new ``Runnable``.
+
         """
         from langchain_core.runnables.passthrough import RunnablePick
 
@@ -706,8 +764,6 @@ class Runnable(ABC, Generic[Input, Output]):
     ) -> RunnableSerializable[Any, Any]:
         """Assigns new fields to the dict output of this ``Runnable``.
 
-        Returns a new ``Runnable``.
-
         .. code-block:: python
 
             from langchain_community.llms.fake import FakeStreamingListLLM
@@ -734,6 +790,13 @@ class Runnable(ABC, Generic[Input, Output]):
             {'str': {'title': 'Str',
             'type': 'string'}, 'hello': {'title': 'Hello', 'type': 'string'}}}
 
+        Args:
+            **kwargs: A mapping of keys to ``Runnable`` or ``Runnable``-like objects
+                that will be invoked with the entire output dict of this ``Runnable``.
+
+        Returns:
+            A new ``Runnable``.
+
         """
         from langchain_core.runnables.passthrough import RunnableAssign
 
@@ -769,12 +832,18 @@ class Runnable(ABC, Generic[Input, Output]):
         config: Optional[RunnableConfig] = None,
         **kwargs: Any,
     ) -> Output:
-        """Default implementation of ``ainvoke``, calls ``invoke`` from a thread.
+        """Transform a single input into an output.
 
-        The default implementation allows usage of async code even if
-        the ``Runnable`` did not implement a native async version of ``invoke``.
+        Args:
+            input: The input to the ``Runnable``.
+            config: A config to use when invoking the ``Runnable``.
+                The config supports standard keys like ``'tags'``, ``'metadata'`` for
+                tracing purposes, ``'max_concurrency'`` for controlling how much work to
+                do in parallel, and other keys. Please refer to the ``RunnableConfig``
+                for more details. Defaults to None.
 
-        Subclasses should override this method if they can run asynchronously.
+        Returns:
+            The output of the ``Runnable``.
 
         """
         return await run_in_executor(config, self.invoke, input, config, **kwargs)
@@ -794,6 +863,20 @@ class Runnable(ABC, Generic[Input, Output]):
         Subclasses should override this method if they can batch more efficiently;
         e.g., if the underlying ``Runnable`` uses an API which supports a batch mode.
 
+        Args:
+             inputs: A list of inputs to the ``Runnable``.
+             config: A config to use when invoking the ``Runnable``.
+                 The config supports standard keys like ``'tags'``, ``'metadata'`` for
+                 tracing purposes, ``'max_concurrency'`` for controlling how much work
+                 to do in parallel, and other keys. Please refer to the
+                 ``RunnableConfig`` for more details. Defaults to None.
+             return_exceptions: Whether to return exceptions instead of raising them.
+                 Defaults to False.
+             **kwargs: Additional keyword arguments to pass to the ``Runnable``.
+
+        Returns:
+             A list of outputs from the ``Runnable``.
+
         """
         if not inputs:
             return []
@@ -848,6 +931,20 @@ class Runnable(ABC, Generic[Input, Output]):
 
         Yields results as they complete.
 
+        Args:
+            inputs: A list of inputs to the ``Runnable``.
+            config: A config to use when invoking the ``Runnable``.
+                The config supports standard keys like ``'tags'``, ``'metadata'`` for
+                tracing purposes, ``'max_concurrency'`` for controlling how much work to
+                do in parallel, and other keys. Please refer to the ``RunnableConfig``
+                for more details. Defaults to None.
+            return_exceptions: Whether to return exceptions instead of raising them.
+                Defaults to False.
+            **kwargs: Additional keyword arguments to pass to the ``Runnable``.
+
+        Yields:
+            Tuples of the index of the input and the output from the ``Runnable``.
+
         """
         if not inputs:
             return
@@ -912,7 +1009,7 @@ class Runnable(ABC, Generic[Input, Output]):
                 for more details. Defaults to None.
             return_exceptions: Whether to return exceptions instead of raising them.
                 Defaults to False.
-            kwargs: Additional keyword arguments to pass to the ``Runnable``.
+            **kwargs: Additional keyword arguments to pass to the ``Runnable``.
 
         Returns:
             A list of outputs from the ``Runnable``.
@@ -2560,6 +2657,9 @@ class RunnableSerializable(Serializable, Runnable[Input, Output]):
         Args:
             **kwargs: A dictionary of ``ConfigurableField`` instances to configure.
 
+        Raises:
+            ValueError: If a configuration key is not found in the ``Runnable``.
+
         Returns:
             A new ``Runnable`` with the fields configured.
 
@@ -2873,6 +2973,11 @@ class RunnableSequence(RunnableSerializable[Input, Output]):
     @classmethod
     @override
     def get_lc_namespace(cls) -> list[str]:
+        """Get the namespace of the langchain object.
+
+        Returns:
+            ``["langchain", "schema", "runnable"]``
+        """
         return ["langchain", "schema", "runnable"]
 
     @property
@@ -2887,14 +2992,7 @@ class RunnableSequence(RunnableSerializable[Input, Output]):
     @classmethod
     @override
     def is_lc_serializable(cls) -> bool:
-        """Check if the object is serializable.
-
-        Returns:
-            True if the object is serializable, False otherwise.
-
-            Defaults to True.
-
-        """
+        """Return True as this class is serializable."""
         return True
 
     model_config = ConfigDict(
@@ -3666,11 +3764,17 @@ class RunnableParallel(RunnableSerializable[Input, dict[str, Any]]):
     @classmethod
     @override
     def is_lc_serializable(cls) -> bool:
+        """Return True as this class is serializable."""
         return True
 
     @classmethod
     @override
     def get_lc_namespace(cls) -> list[str]:
+        """Get the namespace of the langchain object.
+
+        Returns:
+            ``["langchain", "schema", "runnable"]``
+        """
         return ["langchain", "schema", "runnable"]
 
     model_config = ConfigDict(
@@ -4700,7 +4804,7 @@ class RunnableLambda(Runnable[Input, Output]):
     __hash__ = None  # type: ignore[assignment]
 
     def __repr__(self) -> str:
-        """A string representation of this ``Runnable``."""
+        """Return a string representation of this ``Runnable``."""
         if self._repr is None:
             if hasattr(self, "func") and isinstance(self.func, itemgetter):
                 self._repr = f"RunnableLambda({str(self.func)[len('operator.') :]})"
@@ -5213,11 +5317,17 @@ class RunnableEachBase(RunnableSerializable[list[Input], list[Output]]):
     @classmethod
     @override
     def is_lc_serializable(cls) -> bool:
+        """Return True as this class is serializable."""
         return True
 
     @classmethod
     @override
     def get_lc_namespace(cls) -> list[str]:
+        """Get the namespace of the langchain object.
+
+        Returns:
+            ``["langchain", "schema", "runnable"]``
+        """
         return ["langchain", "schema", "runnable"]
 
     def _invoke(
@@ -5537,6 +5647,7 @@ class RunnableBindingBase(RunnableSerializable[Input, Output]):  # type: ignore[
     @classmethod
     @override
     def is_lc_serializable(cls) -> bool:
+        """Return True as this class is serializable."""
         return True
 
     @classmethod
@@ -5544,7 +5655,8 @@ class RunnableBindingBase(RunnableSerializable[Input, Output]):  # type: ignore[
     def get_lc_namespace(cls) -> list[str]:
         """Get the namespace of the langchain object.
 
-        Defaults to ``["langchain", "schema", "runnable"]``.
+        Returns:
+            ``["langchain", "schema", "runnable"]``
         """
         return ["langchain", "schema", "runnable"]
 
diff --git a/libs/core/langchain_core/runnables/branch.py b/libs/core/langchain_core/runnables/branch.py
index cecc8f34b5f..bd8e8c64a76 100644
--- a/libs/core/langchain_core/runnables/branch.py
+++ b/libs/core/langchain_core/runnables/branch.py
@@ -144,12 +144,17 @@ class RunnableBranch(RunnableSerializable[Input, Output]):
 
     @classmethod
     def is_lc_serializable(cls) -> bool:
-        """RunnableBranch is serializable if all its branches are serializable."""
+        """Return True as this class is serializable."""
         return True
 
     @classmethod
     @override
     def get_lc_namespace(cls) -> list[str]:
+        """Get the namespace of the langchain object.
+
+        Returns:
+            ``["langchain", "schema", "runnable"]``
+        """
         return ["langchain", "schema", "runnable"]
 
     @override
@@ -260,7 +265,6 @@ class RunnableBranch(RunnableSerializable[Input, Output]):
     async def ainvoke(
         self, input: Input, config: Optional[RunnableConfig] = None, **kwargs: Any
     ) -> Output:
-        """Async version of invoke."""
         config = ensure_config(config)
         callback_manager = get_async_callback_manager_for_config(config)
         run_manager = await callback_manager.on_chain_start(
@@ -321,9 +325,6 @@ class RunnableBranch(RunnableSerializable[Input, Output]):
 
         Yields:
             The output of the branch that was run.
-
-        Raises:
-            BaseException: If an error occurs during the execution of the Runnable.
         """
         config = ensure_config(config)
         callback_manager = get_callback_manager_for_config(config)
@@ -408,9 +409,6 @@ class RunnableBranch(RunnableSerializable[Input, Output]):
 
         Yields:
             The output of the branch that was run.
-
-        Raises:
-            BaseException: If an error occurs during the execution of the Runnable.
         """
         config = ensure_config(config)
         callback_manager = get_async_callback_manager_for_config(config)
diff --git a/libs/core/langchain_core/runnables/config.py b/libs/core/langchain_core/runnables/config.py
index cc36622b914..98090872a34 100644
--- a/libs/core/langchain_core/runnables/config.py
+++ b/libs/core/langchain_core/runnables/config.py
@@ -125,6 +125,9 @@ def _set_config_context(
 
     Args:
         config (RunnableConfig): The config to set.
+
+    Returns:
+        The token to reset the config and the previous tracing context.
     """
     from langchain_core.tracers.langchain import LangChainTracer
 
@@ -160,6 +163,9 @@ def set_config_context(config: RunnableConfig) -> Generator[Context, None, None]
 
     Args:
         config (RunnableConfig): The config to set.
+
+    Yields:
+        The config context.
     """
     from langsmith.run_helpers import _set_tracing_context
 
@@ -598,9 +604,6 @@ async def run_in_executor(
 
     Returns:
         Output: The output of the function.
-
-    Raises:
-        RuntimeError: If the function raises a StopIteration.
     """
 
     def wrapper() -> T:
diff --git a/libs/core/langchain_core/runnables/configurable.py b/libs/core/langchain_core/runnables/configurable.py
index a0f9f53a06d..46138b64adf 100644
--- a/libs/core/langchain_core/runnables/configurable.py
+++ b/libs/core/langchain_core/runnables/configurable.py
@@ -70,11 +70,17 @@ class DynamicRunnable(RunnableSerializable[Input, Output]):
     @classmethod
     @override
     def is_lc_serializable(cls) -> bool:
+        """Return True as this class is serializable."""
         return True
 
     @classmethod
     @override
     def get_lc_namespace(cls) -> list[str]:
+        """Get the namespace of the langchain object.
+
+        Returns:
+            ``["langchain", "schema", "runnable"]``
+        """
         return ["langchain", "schema", "runnable"]
 
     @property
diff --git a/libs/core/langchain_core/runnables/fallbacks.py b/libs/core/langchain_core/runnables/fallbacks.py
index 7b0b845c206..ede6fcb572d 100644
--- a/libs/core/langchain_core/runnables/fallbacks.py
+++ b/libs/core/langchain_core/runnables/fallbacks.py
@@ -140,6 +140,7 @@ class RunnableWithFallbacks(RunnableSerializable[Input, Output]):
     @classmethod
     @override
     def is_lc_serializable(cls) -> bool:
+        """Return True as this class is serializable."""
         return True
 
     @classmethod
@@ -147,13 +148,18 @@ class RunnableWithFallbacks(RunnableSerializable[Input, Output]):
     def get_lc_namespace(cls) -> list[str]:
         """Get the namespace of the langchain object.
 
-        Defaults to ["langchain", "schema", "runnable"].
+        Returns:
+            ``["langchain", "schema", "runnable"]``
         """
         return ["langchain", "schema", "runnable"]
 
     @property
     def runnables(self) -> Iterator[Runnable[Input, Output]]:
-        """Iterator over the Runnable and its fallbacks."""
+        """Iterator over the Runnable and its fallbacks.
+
+        Yields:
+            The Runnable then its fallbacks.
+        """
         yield self.runnable
         yield from self.fallbacks
 
diff --git a/libs/core/langchain_core/runnables/graph.py b/libs/core/langchain_core/runnables/graph.py
index 20a841d51a8..7dc5ffc2329 100644
--- a/libs/core/langchain_core/runnables/graph.py
+++ b/libs/core/langchain_core/runnables/graph.py
@@ -475,6 +475,10 @@ class Graph:
 
         If there is no such node, or there are multiple, return None.
         When drawing the graph, this node would be the origin.
+
+        Returns:
+            The first node, or None if there is no such node or multiple
+            candidates.
         """
         return _first_node(self)
 
@@ -483,6 +487,10 @@ class Graph:
 
         If there is no such node, or there are multiple, return None.
         When drawing the graph, this node would be the destination.
+
+        Returns:
+            The last node, or None if there is no such node or multiple
+            candidates.
         """
         return _last_node(self)
 
@@ -513,7 +521,11 @@ class Graph:
             self.remove_node(last_node)
 
     def draw_ascii(self) -> str:
-        """Draw the graph as an ASCII art string."""
+        """Draw the graph as an ASCII art string.
+
+        Returns:
+            The ASCII art string.
+        """
         from langchain_core.runnables.graph_ascii import draw_ascii
 
         return draw_ascii(
diff --git a/libs/core/langchain_core/runnables/graph_ascii.py b/libs/core/langchain_core/runnables/graph_ascii.py
index c33353148d8..9c11c585cd1 100644
--- a/libs/core/langchain_core/runnables/graph_ascii.py
+++ b/libs/core/langchain_core/runnables/graph_ascii.py
@@ -50,8 +50,11 @@ class AsciiCanvas:
         """Create an ASCII canvas.
 
         Args:
-            cols (int): number of columns in the canvas. Should be > 1.
-            lines (int): number of lines in the canvas. Should be > 1.
+            cols: number of columns in the canvas. Should be ``> 1``.
+            lines: number of lines in the canvas. Should be ``> 1``.
+
+        Raises:
+            ValueError: if canvas dimensions are invalid.
         """
         if cols <= 1 or lines <= 1:
             msg = "Canvas dimensions should be > 1"
@@ -63,7 +66,11 @@ class AsciiCanvas:
         self.canvas = [[" "] * cols for line in range(lines)]
 
     def draw(self) -> str:
-        """Draws ASCII canvas on the screen."""
+        """Draws ASCII canvas on the screen.
+
+        Returns:
+            The ASCII canvas string.
+        """
         lines = map("".join, self.canvas)
         return os.linesep.join(lines)
 
@@ -71,12 +78,16 @@ class AsciiCanvas:
         """Create a point on ASCII canvas.
 
         Args:
-            x (int): x coordinate. Should be >= 0 and < number of columns in
+            x: x coordinate. Should be ``>= 0`` and ``<`` number of columns in
                 the canvas.
-            y (int): y coordinate. Should be >= 0 an < number of lines in the
+            y: y coordinate. Should be ``>= 0`` an ``<`` number of lines in the
                 canvas.
-            char (str): character to place in the specified point on the
+            char: character to place in the specified point on the
                 canvas.
+
+        Raises:
+            ValueError: if char is not a single character or if
+                coordinates are out of bounds.
         """
         if len(char) != 1:
             msg = "char should be a single character"
@@ -225,11 +236,15 @@ def draw_ascii(vertices: Mapping[str, str], edges: Sequence[LangEdge]) -> str:
     """Build a DAG and draw it in ASCII.
 
     Args:
-        vertices (list): list of graph vertices.
-        edges (list): list of graph edges.
+        vertices: list of graph vertices.
+        edges: list of graph edges.
+
+    Raises:
+        ValueError: if the canvas dimensions are invalid or if
+            edge coordinates are invalid.
 
     Returns:
-        str: ASCII representation
+        ASCII representation
 
     Example:
 
diff --git a/libs/core/langchain_core/runnables/graph_png.py b/libs/core/langchain_core/runnables/graph_png.py
index 504236188ce..c7d15c85127 100644
--- a/libs/core/langchain_core/runnables/graph_png.py
+++ b/libs/core/langchain_core/runnables/graph_png.py
@@ -85,9 +85,6 @@ class PngDrawer:
         Args:
             viz: The graphviz object.
             node: The node to add.
-
-        Returns:
-            None
         """
         viz.add_node(
             node,
@@ -114,9 +111,6 @@ class PngDrawer:
             target: The target node.
             label: The label for the edge. Defaults to None.
             conditional: Whether the edge is conditional. Defaults to False.
-
-        Returns:
-            None
         """
         viz.add_edge(
             source,
@@ -131,8 +125,16 @@ class PngDrawer:
         """Draw the given state graph into a PNG file.
 
         Requires `graphviz` and `pygraphviz` to be installed.
-        :param graph: The graph to draw
-        :param output_path: The path to save the PNG. If None, PNG bytes are returned.
+
+        Args:
+            graph: The graph to draw
+            output_path: The path to save the PNG. If None, PNG bytes are returned.
+
+        Raises:
+            ImportError: If ``pygraphviz`` is not installed.
+
+        Returns:
+            The PNG bytes if ``output_path`` is None, else None.
         """
         try:
             import pygraphviz as pgv  # type: ignore[import-not-found]
diff --git a/libs/core/langchain_core/runnables/passthrough.py b/libs/core/langchain_core/runnables/passthrough.py
index afc28e54d42..848bf264c63 100644
--- a/libs/core/langchain_core/runnables/passthrough.py
+++ b/libs/core/langchain_core/runnables/passthrough.py
@@ -193,11 +193,16 @@ class RunnablePassthrough(RunnableSerializable[Other, Other]):
     @classmethod
     @override
     def is_lc_serializable(cls) -> bool:
+        """Return True as this class is serializable."""
         return True
 
     @classmethod
-    @override
     def get_lc_namespace(cls) -> list[str]:
+        """Get the namespace of the langchain object.
+
+        Returns:
+            ``["langchain", "schema", "runnable"]``
+        """
         return ["langchain", "schema", "runnable"]
 
     @property
@@ -417,11 +422,17 @@ class RunnableAssign(RunnableSerializable[dict[str, Any], dict[str, Any]]):
     @classmethod
     @override
     def is_lc_serializable(cls) -> bool:
+        """Return True as this class is serializable."""
         return True
 
     @classmethod
     @override
     def get_lc_namespace(cls) -> list[str]:
+        """Get the namespace of the langchain object.
+
+        Returns:
+            ``["langchain", "schema", "runnable"]``
+        """
         return ["langchain", "schema", "runnable"]
 
     @override
@@ -721,12 +732,17 @@ class RunnablePick(RunnableSerializable[dict[str, Any], dict[str, Any]]):
     @classmethod
     @override
     def is_lc_serializable(cls) -> bool:
+        """Return True as this class is serializable."""
         return True
 
     @classmethod
     @override
     def get_lc_namespace(cls) -> list[str]:
-        """Get the namespace of the langchain object."""
+        """Get the namespace of the langchain object.
+
+        Returns:
+            ``["langchain", "schema", "runnable"]``
+        """
         return ["langchain", "schema", "runnable"]
 
     @override
diff --git a/libs/core/langchain_core/runnables/router.py b/libs/core/langchain_core/runnables/router.py
index 7cc947fe9a8..827e75c6624 100644
--- a/libs/core/langchain_core/runnables/router.py
+++ b/libs/core/langchain_core/runnables/router.py
@@ -98,13 +98,17 @@ class RouterRunnable(RunnableSerializable[RouterInput, Output]):
     @classmethod
     @override
     def is_lc_serializable(cls) -> bool:
-        """Return whether this class is serializable."""
+        """Return True as this class is serializable."""
         return True
 
     @classmethod
     @override
     def get_lc_namespace(cls) -> list[str]:
-        """Get the namespace of the langchain object."""
+        """Get the namespace of the langchain object.
+
+        Returns:
+            ``["langchain", "schema", "runnable"]``
+        """
         return ["langchain", "schema", "runnable"]
 
     @override
diff --git a/libs/core/langchain_core/runnables/utils.py b/libs/core/langchain_core/runnables/utils.py
index 3a740e868eb..eb4c0cd43d5 100644
--- a/libs/core/langchain_core/runnables/utils.py
+++ b/libs/core/langchain_core/runnables/utils.py
@@ -122,7 +122,12 @@ def accepts_context(callable: Callable[..., Any]) -> bool:  # noqa: A002
 
 @lru_cache(maxsize=1)
 def asyncio_accepts_context() -> bool:
-    """Cache the result of checking if asyncio.create_task accepts a ``context`` arg."""
+    """Cache the result of checking if asyncio.create_task accepts a ``context`` arg.
+
+    Returns:
+        bool: True if ``asyncio.create_task`` accepts a context argument, False
+            otherwise.
+    """
     return accepts_context(asyncio.create_task)
 
 
@@ -160,14 +165,11 @@ class IsLocalDict(ast.NodeVisitor):
         self.keys = keys
 
     @override
-    def visit_Subscript(self, node: ast.Subscript) -> Any:
+    def visit_Subscript(self, node: ast.Subscript) -> None:
         """Visit a subscript node.
 
         Args:
             node: The node to visit.
-
-        Returns:
-            Any: The result of the visit.
         """
         if (
             isinstance(node.ctx, ast.Load)
@@ -180,14 +182,11 @@ class IsLocalDict(ast.NodeVisitor):
             self.keys.add(node.slice.value)
 
     @override
-    def visit_Call(self, node: ast.Call) -> Any:
+    def visit_Call(self, node: ast.Call) -> None:
         """Visit a call node.
 
         Args:
             node: The node to visit.
-
-        Returns:
-            Any: The result of the visit.
         """
         if (
             isinstance(node.func, ast.Attribute)
@@ -210,14 +209,11 @@ class IsFunctionArgDict(ast.NodeVisitor):
         self.keys: set[str] = set()
 
     @override
-    def visit_Lambda(self, node: ast.Lambda) -> Any:
+    def visit_Lambda(self, node: ast.Lambda) -> None:
         """Visit a lambda function.
 
         Args:
             node: The node to visit.
-
-        Returns:
-            Any: The result of the visit.
         """
         if not node.args.args:
             return
@@ -225,14 +221,11 @@ class IsFunctionArgDict(ast.NodeVisitor):
         IsLocalDict(input_arg_name, self.keys).visit(node.body)
 
     @override
-    def visit_FunctionDef(self, node: ast.FunctionDef) -> Any:
+    def visit_FunctionDef(self, node: ast.FunctionDef) -> None:
         """Visit a function definition.
 
         Args:
             node: The node to visit.
-
-        Returns:
-            Any: The result of the visit.
         """
         if not node.args.args:
             return
@@ -240,14 +233,11 @@ class IsFunctionArgDict(ast.NodeVisitor):
         IsLocalDict(input_arg_name, self.keys).visit(node)
 
     @override
-    def visit_AsyncFunctionDef(self, node: ast.AsyncFunctionDef) -> Any:
+    def visit_AsyncFunctionDef(self, node: ast.AsyncFunctionDef) -> None:
         """Visit an async function definition.
 
         Args:
             node: The node to visit.
-
-        Returns:
-            Any: The result of the visit.
         """
         if not node.args.args:
             return
@@ -264,14 +254,11 @@ class NonLocals(ast.NodeVisitor):
         self.stores: set[str] = set()
 
     @override
-    def visit_Name(self, node: ast.Name) -> Any:
+    def visit_Name(self, node: ast.Name) -> None:
         """Visit a name node.
 
         Args:
             node: The node to visit.
-
-        Returns:
-            Any: The result of the visit.
         """
         if isinstance(node.ctx, ast.Load):
             self.loads.add(node.id)
@@ -279,14 +266,11 @@ class NonLocals(ast.NodeVisitor):
             self.stores.add(node.id)
 
     @override
-    def visit_Attribute(self, node: ast.Attribute) -> Any:
+    def visit_Attribute(self, node: ast.Attribute) -> None:
         """Visit an attribute node.
 
         Args:
             node: The node to visit.
-
-        Returns:
-            Any: The result of the visit.
         """
         if isinstance(node.ctx, ast.Load):
             parent = node.value
@@ -321,42 +305,33 @@ class FunctionNonLocals(ast.NodeVisitor):
         self.nonlocals: set[str] = set()
 
     @override
-    def visit_FunctionDef(self, node: ast.FunctionDef) -> Any:
+    def visit_FunctionDef(self, node: ast.FunctionDef) -> None:
         """Visit a function definition.
 
         Args:
             node: The node to visit.
-
-        Returns:
-            Any: The result of the visit.
         """
         visitor = NonLocals()
         visitor.visit(node)
         self.nonlocals.update(visitor.loads - visitor.stores)
 
     @override
-    def visit_AsyncFunctionDef(self, node: ast.AsyncFunctionDef) -> Any:
+    def visit_AsyncFunctionDef(self, node: ast.AsyncFunctionDef) -> None:
         """Visit an async function definition.
 
         Args:
             node: The node to visit.
-
-        Returns:
-            Any: The result of the visit.
         """
         visitor = NonLocals()
         visitor.visit(node)
         self.nonlocals.update(visitor.loads - visitor.stores)
 
     @override
-    def visit_Lambda(self, node: ast.Lambda) -> Any:
+    def visit_Lambda(self, node: ast.Lambda) -> None:
         """Visit a lambda function.
 
         Args:
             node: The node to visit.
-
-        Returns:
-            Any: The result of the visit.
         """
         visitor = NonLocals()
         visitor.visit(node)
@@ -372,14 +347,11 @@ class GetLambdaSource(ast.NodeVisitor):
         self.count = 0
 
     @override
-    def visit_Lambda(self, node: ast.Lambda) -> Any:
+    def visit_Lambda(self, node: ast.Lambda) -> None:
         """Visit a lambda function.
 
         Args:
             node: The node to visit.
-
-        Returns:
-            Any: The result of the visit.
         """
         self.count += 1
         if hasattr(ast, "unparse"):
@@ -496,6 +468,9 @@ class AddableDict(dict[str, Any]):
 
         Args:
             other: The other dictionary to add.
+
+        Returns:
+            A dictionary that is the result of adding the two dictionaries.
         """
         chunk = AddableDict(self)
         for key in other:
@@ -514,6 +489,9 @@ class AddableDict(dict[str, Any]):
 
         Args:
             other: The other dictionary to be added to.
+
+        Returns:
+            A dictionary that is the result of adding the two dictionaries.
         """
         chunk = AddableDict(other)
         for key in self:
diff --git a/libs/core/langchain_core/stores.py b/libs/core/langchain_core/stores.py
index e6df8fd93eb..7f51b4c4b5a 100644
--- a/libs/core/langchain_core/stores.py
+++ b/libs/core/langchain_core/stores.py
@@ -16,6 +16,8 @@ from typing import (
     Union,
 )
 
+from typing_extensions import override
+
 from langchain_core.exceptions import LangChainException
 from langchain_core.runnables import run_in_executor
 
@@ -206,27 +208,13 @@ class InMemoryBaseStore(BaseStore[str, V], Generic[V]):
         """
         return self.mget(keys)
 
+    @override
     def mset(self, key_value_pairs: Sequence[tuple[str, V]]) -> None:
-        """Set the values for the given keys.
-
-        Args:
-            key_value_pairs (Sequence[tuple[str, V]]): A sequence of key-value pairs.
-
-        Returns:
-            None
-        """
         for key, value in key_value_pairs:
             self.store[key] = value
 
+    @override
     async def amset(self, key_value_pairs: Sequence[tuple[str, V]]) -> None:
-        """Async set the values for the given keys.
-
-        Args:
-            key_value_pairs (Sequence[tuple[str, V]]): A sequence of key-value pairs.
-
-        Returns:
-            None
-        """
         return self.mset(key_value_pairs)
 
     def mdelete(self, keys: Sequence[str]) -> None:
diff --git a/libs/core/langchain_core/tools/base.py b/libs/core/langchain_core/tools/base.py
index e93cb74dc6b..d1b18a3aa42 100644
--- a/libs/core/langchain_core/tools/base.py
+++ b/libs/core/langchain_core/tools/base.py
@@ -506,7 +506,12 @@ class ChildTool(BaseTool):
     """
 
     def __init__(self, **kwargs: Any) -> None:
-        """Initialize the tool."""
+        """Initialize the tool.
+
+        Raises:
+            TypeError: If ``args_schema`` is not a subclass of pydantic ``BaseModel`` or
+                dict.
+        """
         if (
             "args_schema" in kwargs
             and kwargs["args_schema"] is not None
@@ -628,9 +633,10 @@ class ChildTool(BaseTool):
             The parsed and validated input.
 
         Raises:
-            ValueError: If string input is provided with JSON schema or if
-                InjectedToolCallId is required but not provided.
-            NotImplementedError: If args_schema is not a supported type.
+            ValueError: If string input is provided with JSON schema ``args_schema``.
+            ValueError: If InjectedToolCallId is required but ``tool_call_id`` is not
+                provided.
+            TypeError: If args_schema is not a Pydantic ``BaseModel`` or dict.
         """
         input_args = self.args_schema
         if isinstance(tool_input, str):
@@ -725,6 +731,9 @@ class ChildTool(BaseTool):
 
         Add run_manager: Optional[CallbackManagerForToolRun] = None
         to child implementations to enable tracing.
+
+        Returns:
+            The result of the tool execution.
         """
 
     async def _arun(self, *args: Any, **kwargs: Any) -> Any:
@@ -732,6 +741,9 @@ class ChildTool(BaseTool):
 
         Add run_manager: Optional[AsyncCallbackManagerForToolRun] = None
         to child implementations to enable tracing.
+
+        Returns:
+            The result of the tool execution.
         """
         if kwargs.get("run_manager") and signature(self._run).parameters.get(
             "run_manager"
@@ -1312,6 +1324,9 @@ def get_all_basemodel_annotations(
     Args:
         cls: The Pydantic BaseModel class.
         default_to_bound: Whether to default to the bound of a TypeVar if it exists.
+
+    Returns:
+        A dictionary of field names to their type annotations.
     """
     # cls has no subscript: cls = FooBar
     if isinstance(cls, type):
diff --git a/libs/core/langchain_core/tools/convert.py b/libs/core/langchain_core/tools/convert.py
index 2693ce80150..84b328f0bed 100644
--- a/libs/core/langchain_core/tools/convert.py
+++ b/libs/core/langchain_core/tools/convert.py
@@ -119,6 +119,17 @@ def tool(
             whether to raise ValueError on invalid Google Style docstrings.
             Defaults to True.
 
+    Raises:
+        ValueError: If too many positional arguments are provided.
+        ValueError: If a runnable is provided without a string name.
+        ValueError: If the first argument is not a string or callable with
+            a ``__name__`` attribute.
+        ValueError: If the function does not have a docstring and description
+            is not provided and ``infer_schema`` is False.
+        ValueError: If ``parse_docstring`` is True and the function has an invalid
+            Google-style docstring and ``error_on_invalid_docstring`` is True.
+        ValueError: If a Runnable is provided that does not have an object schema.
+
     Returns:
         The tool.
 
diff --git a/libs/core/langchain_core/tools/simple.py b/libs/core/langchain_core/tools/simple.py
index 05dc1917644..40c58e372e1 100644
--- a/libs/core/langchain_core/tools/simple.py
+++ b/libs/core/langchain_core/tools/simple.py
@@ -76,7 +76,19 @@ class Tool(BaseTool):
     def _to_args_and_kwargs(
         self, tool_input: Union[str, dict], tool_call_id: Optional[str]
     ) -> tuple[tuple, dict]:
-        """Convert tool input to pydantic model."""
+        """Convert tool input to pydantic model.
+
+        Args:
+            tool_input: The input to the tool.
+            tool_call_id: The ID of the tool call.
+
+        Raises:
+            ToolException: If the tool input is invalid.
+
+        Returns:
+            the pydantic model args and kwargs.
+
+        """
         args, kwargs = super()._to_args_and_kwargs(tool_input, tool_call_id)
         # For backwards compatibility. The tool must be run with a single input
         all_args = list(args) + list(kwargs.values())
@@ -96,7 +108,17 @@ class Tool(BaseTool):
         run_manager: Optional[CallbackManagerForToolRun] = None,
         **kwargs: Any,
     ) -> Any:
-        """Use the tool."""
+        """Use the tool.
+
+        Args:
+            *args: Positional arguments to pass to the tool
+            config: Configuration for the run
+            run_manager: Optional callback manager to use for the run
+            **kwargs: Keyword arguments to pass to the tool
+
+        Returns:
+            The result of the tool execution
+        """
         if self.func:
             if run_manager and signature(self.func).parameters.get("callbacks"):
                 kwargs["callbacks"] = run_manager.get_child()
@@ -113,7 +135,17 @@ class Tool(BaseTool):
         run_manager: Optional[AsyncCallbackManagerForToolRun] = None,
         **kwargs: Any,
     ) -> Any:
-        """Use the tool asynchronously."""
+        """Use the tool asynchronously.
+
+        Args:
+            *args: Positional arguments to pass to the tool
+            config: Configuration for the run
+            run_manager: Optional callback manager to use for the run
+            **kwargs: Keyword arguments to pass to the tool
+
+        Returns:
+            The result of the tool execution
+        """
         if self.coroutine:
             if run_manager and signature(self.coroutine).parameters.get("callbacks"):
                 kwargs["callbacks"] = run_manager.get_child()
diff --git a/libs/core/langchain_core/tools/structured.py b/libs/core/langchain_core/tools/structured.py
index 7fcc3c26e5a..08078e92771 100644
--- a/libs/core/langchain_core/tools/structured.py
+++ b/libs/core/langchain_core/tools/structured.py
@@ -84,7 +84,17 @@ class StructuredTool(BaseTool):
         run_manager: Optional[CallbackManagerForToolRun] = None,
         **kwargs: Any,
     ) -> Any:
-        """Use the tool."""
+        """Use the tool.
+
+        Args:
+            *args: Positional arguments to pass to the tool
+            config: Configuration for the run
+            run_manager: Optional callback manager to use for the run
+            **kwargs: Keyword arguments to pass to the tool
+
+        Returns:
+            The result of the tool execution
+        """
         if self.func:
             if run_manager and signature(self.func).parameters.get("callbacks"):
                 kwargs["callbacks"] = run_manager.get_child()
@@ -101,7 +111,17 @@ class StructuredTool(BaseTool):
         run_manager: Optional[AsyncCallbackManagerForToolRun] = None,
         **kwargs: Any,
     ) -> Any:
-        """Use the tool asynchronously."""
+        """Use the tool asynchronously.
+
+        Args:
+            *args: Positional arguments to pass to the tool
+            config: Configuration for the run
+            run_manager: Optional callback manager to use for the run
+            **kwargs: Keyword arguments to pass to the tool
+
+        Returns:
+            The result of the tool execution
+        """
         if self.coroutine:
             if run_manager and signature(self.coroutine).parameters.get("callbacks"):
                 kwargs["callbacks"] = run_manager.get_child()
@@ -164,6 +184,9 @@ class StructuredTool(BaseTool):
 
         Raises:
             ValueError: If the function is not provided.
+            ValueError: If the function does not have a docstring and description
+                is not provided.
+            TypeError: If the ``args_schema`` is not a ``BaseModel`` or dict.
 
         Examples:
 
diff --git a/libs/core/langchain_core/tracers/base.py b/libs/core/langchain_core/tracers/base.py
index ee588606165..e33f0339af7 100644
--- a/libs/core/langchain_core/tracers/base.py
+++ b/libs/core/langchain_core/tracers/base.py
@@ -520,11 +520,11 @@ class BaseTracer(_TracerCore, BaseCallbackHandler, ABC):
         return retrieval_run
 
     def __deepcopy__(self, memo: dict) -> BaseTracer:
-        """Deepcopy the tracer."""
+        """Return self."""
         return self
 
     def __copy__(self) -> BaseTracer:
-        """Copy the tracer."""
+        """Return self."""
         return self
 
 
diff --git a/libs/core/langchain_core/tracers/context.py b/libs/core/langchain_core/tracers/context.py
index 58471a09ecc..838eaa6d8f5 100644
--- a/libs/core/langchain_core/tracers/context.py
+++ b/libs/core/langchain_core/tracers/context.py
@@ -43,7 +43,11 @@ run_collector_var: ContextVar[Optional[RunCollectorCallbackHandler]] = ContextVa
 def tracing_enabled(
     session_name: str = "default",  # noqa: ARG001
 ) -> Generator[TracerSessionV1, None, None]:
-    """Throw an error because this has been replaced by tracing_v2_enabled."""
+    """Throw an error because this has been replaced by ``tracing_v2_enabled``.
+
+    Raises:
+        RuntimeError: Always, because this function is deprecated.
+    """
     msg = (
         "tracing_enabled is no longer supported. Please use tracing_enabled_v2 instead."
     )
diff --git a/libs/core/langchain_core/tracers/core.py b/libs/core/langchain_core/tracers/core.py
index 0a10b06ecaf..54261a2c224 100644
--- a/libs/core/langchain_core/tracers/core.py
+++ b/libs/core/langchain_core/tracers/core.py
@@ -71,7 +71,7 @@ class _TracerCore(ABC):
                   for streaming events.
                 - 'original+chat' is a format that is the same as 'original'
                   except it does NOT raise an attribute error on_chat_model_start
-            kwargs: Additional keyword arguments that will be passed to
+            **kwargs: Additional keyword arguments that will be passed to
                 the superclass.
         """
         super().__init__(**kwargs)
@@ -531,27 +531,43 @@ class _TracerCore(ABC):
         return retrieval_run
 
     def __deepcopy__(self, memo: dict) -> _TracerCore:
-        """Deepcopy the tracer."""
+        """Return self deepcopied."""
         return self
 
     def __copy__(self) -> _TracerCore:
-        """Copy the tracer."""
+        """Return self copied."""
         return self
 
     def _end_trace(self, run: Run) -> Union[None, Coroutine[Any, Any, None]]:  # noqa: ARG002
-        """End a trace for a run."""
+        """End a trace for a run.
+
+        Args:
+            run: The run.
+        """
         return None
 
     def _on_run_create(self, run: Run) -> Union[None, Coroutine[Any, Any, None]]:  # noqa: ARG002
-        """Process a run upon creation."""
+        """Process a run upon creation.
+
+        Args:
+            run: The created run.
+        """
         return None
 
     def _on_run_update(self, run: Run) -> Union[None, Coroutine[Any, Any, None]]:  # noqa: ARG002
-        """Process a run upon update."""
+        """Process a run upon update.
+
+        Args:
+            run: The updated run.
+        """
         return None
 
     def _on_llm_start(self, run: Run) -> Union[None, Coroutine[Any, Any, None]]:  # noqa: ARG002
-        """Process the LLM Run upon start."""
+        """Process the LLM Run upon start.
+
+        Args:
+            run: The LLM run.
+        """
         return None
 
     def _on_llm_new_token(
@@ -560,53 +576,107 @@ class _TracerCore(ABC):
         token: str,  # noqa: ARG002
         chunk: Optional[Union[GenerationChunk, ChatGenerationChunk]],  # noqa: ARG002
     ) -> Union[None, Coroutine[Any, Any, None]]:
-        """Process new LLM token."""
+        """Process new LLM token.
+
+        Args:
+            run: The LLM run.
+            token: The new token.
+            chunk: Optional chunk.
+        """
         return None
 
     def _on_llm_end(self, run: Run) -> Union[None, Coroutine[Any, Any, None]]:  # noqa: ARG002
-        """Process the LLM Run."""
+        """Process the LLM Run.
+
+        Args:
+            run: The LLM run.
+        """
         return None
 
     def _on_llm_error(self, run: Run) -> Union[None, Coroutine[Any, Any, None]]:  # noqa: ARG002
-        """Process the LLM Run upon error."""
+        """Process the LLM Run upon error.
+
+        Args:
+            run: The LLM run.
+        """
         return None
 
     def _on_chain_start(self, run: Run) -> Union[None, Coroutine[Any, Any, None]]:  # noqa: ARG002
-        """Process the Chain Run upon start."""
+        """Process the Chain Run upon start.
+
+        Args:
+            run: The chain run.
+        """
         return None
 
     def _on_chain_end(self, run: Run) -> Union[None, Coroutine[Any, Any, None]]:  # noqa: ARG002
-        """Process the Chain Run."""
+        """Process the Chain Run.
+
+        Args:
+            run: The chain run.
+        """
         return None
 
     def _on_chain_error(self, run: Run) -> Union[None, Coroutine[Any, Any, None]]:  # noqa: ARG002
-        """Process the Chain Run upon error."""
+        """Process the Chain Run upon error.
+
+        Args:
+            run: The chain run.
+        """
         return None
 
     def _on_tool_start(self, run: Run) -> Union[None, Coroutine[Any, Any, None]]:  # noqa: ARG002
-        """Process the Tool Run upon start."""
+        """Process the Tool Run upon start.
+
+        Args:
+            run: The tool run.
+        """
         return None
 
     def _on_tool_end(self, run: Run) -> Union[None, Coroutine[Any, Any, None]]:  # noqa: ARG002
-        """Process the Tool Run."""
+        """Process the Tool Run.
+
+        Args:
+            run: The tool run.
+        """
         return None
 
     def _on_tool_error(self, run: Run) -> Union[None, Coroutine[Any, Any, None]]:  # noqa: ARG002
-        """Process the Tool Run upon error."""
+        """Process the Tool Run upon error.
+
+        Args:
+            run: The tool run.
+        """
         return None
 
     def _on_chat_model_start(self, run: Run) -> Union[None, Coroutine[Any, Any, None]]:  # noqa: ARG002
-        """Process the Chat Model Run upon start."""
+        """Process the Chat Model Run upon start.
+
+        Args:
+            run: The chat model run.
+        """
         return None
 
     def _on_retriever_start(self, run: Run) -> Union[None, Coroutine[Any, Any, None]]:  # noqa: ARG002
-        """Process the Retriever Run upon start."""
+        """Process the Retriever Run upon start.
+
+        Args:
+            run: The retriever run.
+        """
         return None
 
     def _on_retriever_end(self, run: Run) -> Union[None, Coroutine[Any, Any, None]]:  # noqa: ARG002
-        """Process the Retriever Run."""
+        """Process the Retriever Run.
+
+        Args:
+            run: The retriever run.
+        """
         return None
 
     def _on_retriever_error(self, run: Run) -> Union[None, Coroutine[Any, Any, None]]:  # noqa: ARG002
-        """Process the Retriever Run upon error."""
+        """Process the Retriever Run upon error.
+
+        Args:
+            run: The retriever run.
+        """
         return None
diff --git a/libs/core/langchain_core/tracers/event_stream.py b/libs/core/langchain_core/tracers/event_stream.py
index eff11bbb06a..b0e44d4eca1 100644
--- a/libs/core/langchain_core/tracers/event_stream.py
+++ b/libs/core/langchain_core/tracers/event_stream.py
@@ -155,7 +155,11 @@ class _AstreamEventsCallbackHandler(AsyncCallbackHandler, _StreamingCallbackHand
             self.send_stream.send_nowait(event)
 
     def __aiter__(self) -> AsyncIterator[Any]:
-        """Iterate over the receive stream."""
+        """Iterate over the receive stream.
+
+        Returns:
+            An async iterator over the receive stream.
+        """
         return self.receive_stream.__aiter__()
 
     async def tap_output_aiter(
@@ -412,7 +416,6 @@ class _AstreamEventsCallbackHandler(AsyncCallbackHandler, _StreamingCallbackHand
         parent_run_id: Optional[UUID] = None,
         **kwargs: Any,
     ) -> None:
-        """Run on new LLM token. Only available when streaming is enabled."""
         run_info = self.run_map.get(run_id)
         chunk_: Union[GenerationChunk, BaseMessageChunk]
 
@@ -458,7 +461,15 @@ class _AstreamEventsCallbackHandler(AsyncCallbackHandler, _StreamingCallbackHand
     async def on_llm_end(
         self, response: LLMResult, *, run_id: UUID, **kwargs: Any
     ) -> None:
-        """End a trace for an LLM run."""
+        """End a trace for an LLM run.
+
+        Args:
+            response (LLMResult): The response which was generated.
+            run_id (UUID): The run ID. This is the ID of the current run.
+
+        Raises:
+            ValueError: If the run type is not ``'llm'`` or ``'chat_model'``.
+        """
         run_info = self.run_map.pop(run_id)
         inputs_ = run_info["inputs"]
 
@@ -636,7 +647,15 @@ class _AstreamEventsCallbackHandler(AsyncCallbackHandler, _StreamingCallbackHand
 
     @override
     async def on_tool_end(self, output: Any, *, run_id: UUID, **kwargs: Any) -> None:
-        """End a trace for a tool run."""
+        """End a trace for a tool run.
+
+        Args:
+            output: The output of the tool.
+            run_id: The run ID. This is the ID of the current run.
+
+        Raises:
+            AssertionError: If the run ID is a tool call and does not have inputs
+        """
         run_info = self.run_map.pop(run_id)
         if "inputs" not in run_info:
             msg = (
@@ -730,11 +749,11 @@ class _AstreamEventsCallbackHandler(AsyncCallbackHandler, _StreamingCallbackHand
         )
 
     def __deepcopy__(self, memo: dict) -> _AstreamEventsCallbackHandler:
-        """Deepcopy the tracer."""
+        """Return self."""
         return self
 
     def __copy__(self) -> _AstreamEventsCallbackHandler:
-        """Copy the tracer."""
+        """Return self."""
         return self
 
 
diff --git a/libs/core/langchain_core/tracers/langchain.py b/libs/core/langchain_core/tracers/langchain.py
index 4a6d0d82344..07e6618573e 100644
--- a/libs/core/langchain_core/tracers/langchain.py
+++ b/libs/core/langchain_core/tracers/langchain.py
@@ -53,7 +53,11 @@ def wait_for_all_tracers() -> None:
 
 
 def get_client() -> Client:
-    """Get the client."""
+    """Get the client.
+
+    Returns:
+        The LangSmith client.
+    """
     return rt.get_cached_client()
 
 
@@ -235,7 +239,6 @@ class LangChainTracer(BaseTracer):
         chunk: Optional[Union[GenerationChunk, ChatGenerationChunk]] = None,
         parent_run_id: Optional[UUID] = None,
     ) -> Run:
-        """Append token event to LLM run and return the run."""
         run_id_str = str(run_id)
         if run_id_str not in self.run_has_token_event_map:
             self.run_has_token_event_map[run_id_str] = True
diff --git a/libs/core/langchain_core/tracers/langchain_v1.py b/libs/core/langchain_core/tracers/langchain_v1.py
index 63aab51eeea..92634f5c912 100644
--- a/libs/core/langchain_core/tracers/langchain_v1.py
+++ b/libs/core/langchain_core/tracers/langchain_v1.py
@@ -7,7 +7,11 @@ from typing import Any
 
 
 def get_headers(*args: Any, **kwargs: Any) -> Any:  # noqa: ARG001
-    """Throw an error because this has been replaced by get_headers."""
+    """Throw an error because this has been replaced by get_headers.
+
+    Raises:
+        RuntimeError: Always, because this function is deprecated.
+    """
     msg = (
         "get_headers for LangChainTracerV1 is no longer supported. "
         "Please use LangChainTracer instead."
@@ -16,7 +20,11 @@ def get_headers(*args: Any, **kwargs: Any) -> Any:  # noqa: ARG001
 
 
 def LangChainTracerV1(*args: Any, **kwargs: Any) -> Any:  # noqa: N802,ARG001
-    """Throw an error because this has been replaced by LangChainTracer."""
+    """Throw an error because this has been replaced by ``LangChainTracer``.
+
+    Raises:
+        RuntimeError: Always, because this class is deprecated.
+    """
     msg = (
         "LangChainTracerV1 is no longer supported. Please use LangChainTracer instead."
     )
diff --git a/libs/core/langchain_core/tracers/log_stream.py b/libs/core/langchain_core/tracers/log_stream.py
index dbf5ef2a6ae..2821ade0dc5 100644
--- a/libs/core/langchain_core/tracers/log_stream.py
+++ b/libs/core/langchain_core/tracers/log_stream.py
@@ -110,7 +110,17 @@ class RunLogPatch:
         self.ops = list(ops)
 
     def __add__(self, other: Union[RunLogPatch, Any]) -> RunLog:
-        """Combine two RunLogPatch instances."""
+        """Combine two ``RunLogPatch`` instances.
+
+        Args:
+            other: The other ``RunLogPatch`` to combine with.
+
+        Raises:
+            TypeError: If the other object is not a ``RunLogPatch``.
+
+        Returns:
+            A new ``RunLog`` representing the combination of the two.
+        """
         if type(other) is RunLogPatch:
             ops = self.ops + other.ops
             state = jsonpatch.apply_patch(None, copy.deepcopy(ops))
@@ -150,7 +160,17 @@ class RunLog(RunLogPatch):
         self.state = state
 
     def __add__(self, other: Union[RunLogPatch, Any]) -> RunLog:
-        """Combine two RunLogs."""
+        """Combine two ``RunLog``s.
+
+        Args:
+            other: The other ``RunLog`` or ``RunLogPatch`` to combine with.
+
+        Raises:
+            TypeError: If the other object is not a ``RunLog`` or ``RunLogPatch``.
+
+        Returns:
+            A new ``RunLog`` representing the combination of the two.
+        """
         if type(other) is RunLogPatch:
             ops = self.ops + other.ops
             state = jsonpatch.apply_patch(self.state, other.ops)
@@ -167,7 +187,14 @@ class RunLog(RunLogPatch):
 
     @override
     def __eq__(self, other: object) -> bool:
-        """Check if two RunLogs are equal."""
+        """Check if two ``RunLog``s are equal.
+
+        Args:
+            other: The other ``RunLog`` to compare to.
+
+        Returns:
+            True if the ``RunLog``s are equal, False otherwise.
+        """
         # First compare that the state is the same
         if not isinstance(other, RunLog):
             return False
@@ -250,7 +277,11 @@ class LogStreamCallbackHandler(BaseTracer, _StreamingCallbackHandler):
         self.root_id: Optional[UUID] = None
 
     def __aiter__(self) -> AsyncIterator[RunLogPatch]:
-        """Iterate over the stream of run logs."""
+        """Iterate over the stream of run logs.
+
+        Returns:
+            An async iterator over the run log patches.
+        """
         return self.receive_stream.__aiter__()
 
     def send(self, *ops: dict[str, Any]) -> bool:
@@ -623,6 +654,23 @@ async def _astream_log_implementation(
 
     The implementation has been factored out (at least temporarily) as both
     astream_log and astream_events relies on it.
+
+    Args:
+        runnable: The runnable to run in streaming mode.
+        value: The input to the runnable.
+        config: The config to pass to the runnable.
+        stream: The stream to send the run logs to.
+        diff: Whether to yield run log patches (True) or full run logs (False).
+        with_streamed_output_list: Whether to include a list of all streamed
+            outputs in each patch. If False, only the final output will be included
+            in the patches.
+        **kwargs: Additional keyword arguments to pass to the runnable.
+
+    Raises:
+        ValueError: If the callbacks in the config are of an unexpected type.
+
+    Yields:
+        The run log patches or states, depending on the value of ``diff``.
     """
     import jsonpatch
 
diff --git a/libs/core/langchain_core/tracers/schemas.py b/libs/core/langchain_core/tracers/schemas.py
index ea06cb2f9dc..cd3dd71fea7 100644
--- a/libs/core/langchain_core/tracers/schemas.py
+++ b/libs/core/langchain_core/tracers/schemas.py
@@ -18,7 +18,11 @@ from langchain_core._api import deprecated
 
 @deprecated("0.1.0", alternative="Use string instead.", removal="1.0")
 def RunTypeEnum() -> type[RunTypeEnumDep]:  # noqa: N802
-    """RunTypeEnum."""
+    """``RunTypeEnum``.
+
+    Returns:
+        The ``RunTypeEnum`` class.
+    """
     warnings.warn(
         "RunTypeEnum is deprecated. Please directly use a string instead"
         " (e.g. 'llm', 'chain', 'tool').",
diff --git a/libs/core/langchain_core/utils/aiter.py b/libs/core/langchain_core/utils/aiter.py
index 701a2321726..7a0477c658e 100644
--- a/libs/core/langchain_core/utils/aiter.py
+++ b/libs/core/langchain_core/utils/aiter.py
@@ -94,7 +94,7 @@ class NoLock:
         exc_val: Optional[BaseException],
         exc_tb: Optional[TracebackType],
     ) -> bool:
-        """Exception not handled."""
+        """Return False, exception not suppressed."""
         return False
 
 
@@ -236,7 +236,11 @@ class Tee(Generic[T]):
         return self._children[item]
 
     def __iter__(self) -> Iterator[AsyncIterator[T]]:
-        """Iterate over the child iterators."""
+        """Iterate over the child iterators.
+
+        Yields:
+            The child iterators.
+        """
         yield from self._children
 
     async def __aenter__(self) -> "Tee[T]":
@@ -249,7 +253,11 @@ class Tee(Generic[T]):
         exc_val: Optional[BaseException],
         exc_tb: Optional[TracebackType],
     ) -> bool:
-        """Close all child iterators."""
+        """Close all child iterators.
+
+        Returns:
+            False, exceptions not suppressed.
+        """
         await self.aclose()
         return False
 
@@ -318,8 +326,8 @@ async def abatch_iterate(
         size: The size of the batch.
         iterable: The async iterable to batch.
 
-    Returns:
-        An async iterator over the batches.
+    Yields:
+        The batches.
     """
     batch: list[T] = []
     async for element in iterable:
diff --git a/libs/core/langchain_core/utils/env.py b/libs/core/langchain_core/utils/env.py
index 9f37b3c4f47..51fd3d66e21 100644
--- a/libs/core/langchain_core/utils/env.py
+++ b/libs/core/langchain_core/utils/env.py
@@ -39,6 +39,9 @@ def get_from_dict_or_env(
             in the dictionary.
         default: The default value to return if the key is not in the dictionary
             or the environment. Defaults to None.
+
+    Returns:
+        The dict value or the environment variable value.
     """
     if isinstance(key, (list, tuple)):
         for k in key:
diff --git a/libs/core/langchain_core/utils/function_calling.py b/libs/core/langchain_core/utils/function_calling.py
index 61849113d1b..fff700651ea 100644
--- a/libs/core/langchain_core/utils/function_calling.py
+++ b/libs/core/langchain_core/utils/function_calling.py
@@ -146,6 +146,9 @@ def _convert_pydantic_to_openai_function(
             of the schema will be used.
         rm_titles: Whether to remove titles from the schema. Defaults to True.
 
+    Raises:
+        TypeError: If the model is not a Pydantic model.
+
     Returns:
         The function description.
     """
@@ -323,6 +326,9 @@ def _format_tool_to_openai_function(tool: BaseTool) -> FunctionDescription:
     Args:
         tool: The tool to format.
 
+    Raises:
+        ValueError: If the tool call schema is not supported.
+
     Returns:
         The function description.
     """
@@ -602,7 +608,20 @@ def convert_to_json_schema(
     *,
     strict: Optional[bool] = None,
 ) -> dict[str, Any]:
-    """Convert a schema representation to a JSON schema."""
+    """Convert a schema representation to a JSON schema.
+
+    Args:
+        schema: The schema to convert.
+        strict: If True, model output is guaranteed to exactly match the JSON Schema
+            provided in the function definition. If None, ``strict`` argument will not
+            be included in function definition.
+
+    Raises:
+        ValueError: If the input is not a valid OpenAI-format tool.
+
+    Returns:
+        A JSON schema representation of the input schema.
+    """
     openai_tool = convert_to_openai_tool(schema, strict=strict)
     if (
         not isinstance(openai_tool, dict)
diff --git a/libs/core/langchain_core/utils/interactive_env.py b/libs/core/langchain_core/utils/interactive_env.py
index 12676d0bd52..b974b3091eb 100644
--- a/libs/core/langchain_core/utils/interactive_env.py
+++ b/libs/core/langchain_core/utils/interactive_env.py
@@ -2,7 +2,11 @@
 
 
 def is_interactive_env() -> bool:
-    """Determine if running within IPython or Jupyter."""
+    """Determine if running within IPython or Jupyter.
+
+    Returns:
+        True if running in an interactive environment, False otherwise.
+    """
     import sys
 
     return hasattr(sys, "ps2")
diff --git a/libs/core/langchain_core/utils/iter.py b/libs/core/langchain_core/utils/iter.py
index ecd4ba60976..5ef7c98b048 100644
--- a/libs/core/langchain_core/utils/iter.py
+++ b/libs/core/langchain_core/utils/iter.py
@@ -31,7 +31,7 @@ class NoLock:
         exc_val: Optional[BaseException],
         exc_tb: Optional[TracebackType],
     ) -> Literal[False]:
-        """Exception not handled."""
+        """Return False (exception not suppressed)."""
         return False
 
 
@@ -173,7 +173,11 @@ class Tee(Generic[T]):
         return self._children[item]
 
     def __iter__(self) -> Iterator[Iterator[T]]:
-        """Return an iterator over the child iterators."""
+        """Return an iterator over the child iterators.
+
+        Yields:
+            The child iterators.
+        """
         yield from self._children
 
     def __enter__(self) -> "Tee[T]":
@@ -186,7 +190,11 @@ class Tee(Generic[T]):
         exc_val: Optional[BaseException],
         exc_tb: Optional[TracebackType],
     ) -> Literal[False]:
-        """Close all child iterators."""
+        """Close all child iterators.
+
+        Returns:
+            False (exception not suppressed).
+        """
         self.close()
         return False
 
diff --git a/libs/core/langchain_core/utils/json.py b/libs/core/langchain_core/utils/json.py
index 98450587e1c..1306bb9d73c 100644
--- a/libs/core/langchain_core/utils/json.py
+++ b/libs/core/langchain_core/utils/json.py
@@ -26,6 +26,9 @@ def _custom_parser(multiline_string: Union[str, bytes, bytearray]) -> str:
     string containing unescaped newlines, tabs or quotes. This function
     replaces those characters with their escaped counterparts.
     (newlines in JSON must be double-escaped: `\\n`).
+
+    Returns:
+        The modified string with escaped newlines, tabs and quotes.
     """
     if isinstance(multiline_string, (bytes, bytearray)):
         multiline_string = multiline_string.decode()
diff --git a/libs/core/langchain_core/utils/json_schema.py b/libs/core/langchain_core/utils/json_schema.py
index 5463c245b41..2c0672ab645 100644
--- a/libs/core/langchain_core/utils/json_schema.py
+++ b/libs/core/langchain_core/utils/json_schema.py
@@ -49,10 +49,14 @@ def _dereference_refs_helper(
     """Inline every pure {'$ref':...}.
 
     But:
+
     - if shallow_refs=True: only break cycles, do not inline nested refs
     - if shallow_refs=False: deep-inline all nested refs
 
     Also skip recursion under any key in skip_keys.
+
+    Returns:
+        The object with refs dereferenced.
     """
     if processed_refs is None:
         processed_refs = set()
@@ -118,6 +122,9 @@ def dereference_refs(
             shallow-inline refs.
         - If provided (even as an empty list), we will recurse under every key and
             deep-inline all refs.
+
+    Returns:
+        The schema with refs dereferenced.
     """
     full = full_schema or schema_obj
     keys_to_skip = list(skip_keys) if skip_keys is not None else ["$defs"]
diff --git a/libs/core/langchain_core/utils/loading.py b/libs/core/langchain_core/utils/loading.py
index 7921f6a06c1..55066a7bf45 100644
--- a/libs/core/langchain_core/utils/loading.py
+++ b/libs/core/langchain_core/utils/loading.py
@@ -19,7 +19,11 @@ def try_load_from_hub(
     *args: Any,  # noqa: ARG001
     **kwargs: Any,  # noqa: ARG001
 ) -> Any:
-    """[DEPRECATED] Try to load from the old Hub."""
+    """[DEPRECATED] Try to load from the old Hub.
+
+    Returns:
+        None always, indicating that we shouldn't load from the old hub.
+    """
     warnings.warn(
         "Loading from the deprecated github-based Hub is no longer supported. "
         "Please use the new LangChain Hub at https://smith.langchain.com/hub instead.",
diff --git a/libs/core/langchain_core/utils/mustache.py b/libs/core/langchain_core/utils/mustache.py
index 12cab8da0a3..fd2ae359176 100644
--- a/libs/core/langchain_core/utils/mustache.py
+++ b/libs/core/langchain_core/utils/mustache.py
@@ -214,17 +214,22 @@ def tokenize(
         def_rdel: The default right delimiter
             ("}}" by default, as in spec compliant mustache)
 
-    Returns:
-        A generator of mustache tags in the form of a tuple (tag_type, tag_key)
-            Where tag_type is one of:
-             * literal
-             * section
-             * inverted section
-             * end
-             * partial
-             * no escape
-            And tag_key is either the key or in the case of a literal tag,
-            the literal itself.
+    Yields:
+        Mustache tags in the form of a tuple (tag_type, tag_key)
+        where tag_type is one of:
+
+        * literal
+        * section
+        * inverted section
+        * end
+        * partial
+        * no escape
+
+        and tag_key is either the key or in the case of a literal tag,
+        the literal itself.
+
+    Raises:
+        ChevronError: If there is a syntax error in the template.
     """
     global _CURRENT_LINE, _LAST_TAG_LINE
     _CURRENT_LINE = 1
@@ -326,7 +331,7 @@ def tokenize(
 
 
 def _html_escape(string: str) -> str:
-    """HTML escape all of these " & < >."""
+    """Return the HTML-escaped string with these characters escaped: ``" & < >``."""
     html_codes = {
         '"': "&quot;",
         "<": "&lt;",
@@ -349,7 +354,7 @@ def _get_key(
     def_ldel: str,
     def_rdel: str,
 ) -> Any:
-    """Get a key from the current scope."""
+    """Return a key from the current scope."""
     # If the key is a dot
     if key == ".":
         # Then just return the current scope
@@ -407,7 +412,11 @@ def _get_key(
 
 
 def _get_partial(name: str, partials_dict: Mapping[str, str]) -> str:
-    """Load a partial."""
+    """Load a partial.
+
+    Returns:
+        The partial.
+    """
     try:
         # Maybe the partial is in the dictionary
         return partials_dict[name]
diff --git a/libs/core/langchain_core/utils/pydantic.py b/libs/core/langchain_core/utils/pydantic.py
index 08cd7c4522f..272868032d3 100644
--- a/libs/core/langchain_core/utils/pydantic.py
+++ b/libs/core/langchain_core/utils/pydantic.py
@@ -57,6 +57,9 @@ def get_pydantic_major_version() -> int:
     """DEPRECATED - Get the major version of Pydantic.
 
     Use PYDANTIC_VERSION.major instead.
+
+    Returns:
+        The major version of Pydantic.
     """
     return PYDANTIC_VERSION.major
 
@@ -74,12 +77,20 @@ TBaseModel = TypeVar("TBaseModel", bound=PydanticBaseModel)
 
 
 def is_pydantic_v1_subclass(cls: type) -> bool:
-    """Check if the installed Pydantic version is 1.x-like."""
+    """Check if the given class is Pydantic v1-like.
+
+    Returns:
+        True if the given class is a subclass of Pydantic ``BaseModel`` 1.x.
+    """
     return issubclass(cls, BaseModelV1)
 
 
 def is_pydantic_v2_subclass(cls: type) -> bool:
-    """Check if the installed Pydantic version is 1.x-like."""
+    """Check if the given class is Pydantic v2-like.
+
+    Returns:
+        True if the given class is a subclass of Pydantic BaseModel 2.x.
+    """
     return issubclass(cls, BaseModel)
 
 
@@ -90,6 +101,9 @@ def is_basemodel_subclass(cls: type) -> bool:
 
     * pydantic.BaseModel in Pydantic 2.x
     * pydantic.v1.BaseModel in Pydantic 2.x
+
+    Returns:
+        True if the given class is a subclass of Pydantic ``BaseModel``.
     """
     # Before we can use issubclass on the cls we need to check if it is a class
     if not inspect.isclass(cls) or isinstance(cls, GenericAlias):
@@ -105,6 +119,9 @@ def is_basemodel_instance(obj: Any) -> bool:
 
     * pydantic.BaseModel in Pydantic 2.x
     * pydantic.v1.BaseModel in Pydantic 2.x
+
+    Returns:
+        True if the given class is an instance of Pydantic ``BaseModel``.
     """
     return isinstance(obj, (BaseModel, BaseModelV1))
 
@@ -262,7 +279,11 @@ def _create_subset_model(
     descriptions: Optional[dict] = None,
     fn_description: Optional[str] = None,
 ) -> type[BaseModel]:
-    """Create subset model using the same pydantic version as the input model."""
+    """Create subset model using the same pydantic version as the input model.
+
+    Returns:
+        The created subset model.
+    """
     if issubclass(model, BaseModelV1):
         return _create_subset_model_v1(
             name,
@@ -299,7 +320,14 @@ def get_fields(model: BaseModelV1) -> dict[str, ModelField]: ...
 def get_fields(
     model: Union[type[Union[BaseModel, BaseModelV1]], BaseModel, BaseModelV1],
 ) -> Union[dict[str, FieldInfoV2], dict[str, ModelField]]:
-    """Get the field names of a Pydantic model."""
+    """Return the field names of a Pydantic model.
+
+    Args:
+        model: The Pydantic model or instance.
+
+    Raises:
+        TypeError: If the model is not a Pydantic model.
+    """
     if hasattr(model, "model_fields"):
         return model.model_fields
 
diff --git a/libs/core/langchain_core/utils/utils.py b/libs/core/langchain_core/utils/utils.py
index a7467ec51e9..1a41b63dc28 100644
--- a/libs/core/langchain_core/utils/utils.py
+++ b/libs/core/langchain_core/utils/utils.py
@@ -21,17 +21,14 @@ from langchain_core.utils.pydantic import (
 
 
 def xor_args(*arg_groups: tuple[str, ...]) -> Callable:
-    """Validate specified keyword args are mutually exclusive.".
+    """Validate specified keyword args are mutually exclusive.
 
     Args:
         *arg_groups (tuple[str, ...]): Groups of mutually exclusive keyword args.
 
     Returns:
         Callable: Decorator that validates the specified keyword args
-            are mutually exclusive
-
-    Raises:
-        ValueError: If more than one arg in a group is defined.
+            are mutually exclusive.
     """
 
     def decorator(func: Callable) -> Callable:
@@ -381,10 +378,21 @@ def from_env(
         error_message: the error message which will be raised if the key is not found
             and no default value is provided.
             This will be raised as a ValueError.
+
+    Returns:
+        factory method that will look up the value from the environment.
     """
 
     def get_from_env_fn() -> Optional[str]:
-        """Get a value from an environment variable."""
+        """Get a value from an environment variable.
+
+        Raises:
+            ValueError: If the environment variable is not set and no default is
+                provided.
+
+        Returns:
+            The value from the environment.
+        """
         if isinstance(key, (list, tuple)):
             for k in key:
                 if k in os.environ:
@@ -445,7 +453,15 @@ def secret_from_env(
     """
 
     def get_secret_from_env() -> Optional[SecretStr]:
-        """Get a value from an environment variable."""
+        """Get a value from an environment variable.
+
+        Raises:
+            ValueError: If the environment variable is not set and no default is
+                provided.
+
+        Returns:
+            The secret from the environment.
+        """
         if isinstance(key, (list, tuple)):
             for k in key:
                 if k in os.environ:
diff --git a/libs/core/langchain_core/vectorstores/base.py b/libs/core/langchain_core/vectorstores/base.py
index 17fa6592c72..2c4425c9c5a 100644
--- a/libs/core/langchain_core/vectorstores/base.py
+++ b/libs/core/langchain_core/vectorstores/base.py
@@ -270,9 +270,6 @@ class VectorStore(ABC):
 
         Returns:
             List of IDs of the added texts.
-
-        Raises:
-            ValueError: If the number of ids does not match the number of documents.
         """
         if type(self).add_texts != VectorStore.add_texts:
             if "ids" not in kwargs:
@@ -303,9 +300,6 @@ class VectorStore(ABC):
 
         Returns:
             List of IDs of the added texts.
-
-        Raises:
-            ValueError: If the number of IDs does not match the number of documents.
         """
         # If the async method has been overridden, we'll use that.
         if type(self).aadd_texts != VectorStore.aadd_texts:
diff --git a/libs/core/langchain_core/vectorstores/in_memory.py b/libs/core/langchain_core/vectorstores/in_memory.py
index e7787f8a882..0395478dfe9 100644
--- a/libs/core/langchain_core/vectorstores/in_memory.py
+++ b/libs/core/langchain_core/vectorstores/in_memory.py
@@ -189,7 +189,6 @@ class InMemoryVectorStore(VectorStore):
         ids: Optional[list[str]] = None,
         **kwargs: Any,
     ) -> list[str]:
-        """Add documents to the store."""
         texts = [doc.page_content for doc in documents]
         vectors = self.embedding.embed_documents(texts)
 
@@ -223,7 +222,6 @@ class InMemoryVectorStore(VectorStore):
     async def aadd_documents(
         self, documents: list[Document], ids: Optional[list[str]] = None, **kwargs: Any
     ) -> list[str]:
-        """Add documents to the store."""
         texts = [doc.page_content for doc in documents]
         vectors = await self.embedding.aembed_documents(texts)