diff --git a/.github/scripts/get_min_versions.py b/.github/scripts/get_min_versions.py
index dc173c2e0f8..653f6902a47 100644
--- a/.github/scripts/get_min_versions.py
+++ b/.github/scripts/get_min_versions.py
@@ -48,7 +48,7 @@ def get_pypi_versions(package_name: str) -> List[str]:
         KeyError: If package not found or response format unexpected
     """
     pypi_url = f"https://pypi.org/pypi/{package_name}/json"
-    response = requests.get(pypi_url)
+    response = requests.get(pypi_url, timeout=10.0)
     response.raise_for_status()
     return list(response.json()["releases"].keys())
 
diff --git a/libs/langchain/tests/unit_tests/test_pytest_config.py b/libs/langchain/tests/unit_tests/test_pytest_config.py
index c2b0af645fb..b02d3d3dd55 100644
--- a/libs/langchain/tests/unit_tests/test_pytest_config.py
+++ b/libs/langchain/tests/unit_tests/test_pytest_config.py
@@ -8,4 +8,4 @@ def test_socket_disabled() -> None:
     with pytest.raises(pytest_socket.SocketBlockedError):
         # Ignore S113 since we don't need a timeout here as the request
         # should fail immediately
-        requests.get("https://www.example.com")  # noqa: S113
+        requests.get("https://www.example.com", timeout=10.0)  # noqa: S113
diff --git a/libs/partners/anthropic/tests/integration_tests/test_chat_models.py b/libs/partners/anthropic/tests/integration_tests/test_chat_models.py
index 8ef75edb455..6ab3b798fb5 100644
--- a/libs/partners/anthropic/tests/integration_tests/test_chat_models.py
+++ b/libs/partners/anthropic/tests/integration_tests/test_chat_models.py
@@ -1231,7 +1231,7 @@ def test_image_tool_calling() -> None:
         },
     ]
     image_url = "https://raw.githubusercontent.com/langchain-ai/docs/4d11d08b6b0e210bd456943f7a22febbd168b543/src/images/agentic-rag-output.png"
-    image_data = b64encode(httpx.get(image_url).content).decode("utf-8")
+    image_data = b64encode(httpx.get(image_url, timeout=10.0).content).decode("utf-8")
     human_content.append(
         {
             "type": "image",
diff --git a/libs/partners/openai/tests/integration_tests/chat_models/test_base.py b/libs/partners/openai/tests/integration_tests/chat_models/test_base.py
index 26a8bb787a2..28012204af2 100644
--- a/libs/partners/openai/tests/integration_tests/chat_models/test_base.py
+++ b/libs/partners/openai/tests/integration_tests/chat_models/test_base.py
@@ -718,7 +718,7 @@ def test_image_token_counting_jpeg() -> None:
     actual = model.get_num_tokens_from_messages([message])
     assert expected == actual
 
-    image_data = base64.b64encode(httpx.get(image_url).content).decode("utf-8")
+    image_data = base64.b64encode(httpx.get(image_url, timeout=10.0).content).decode("utf-8")
     message = HumanMessage(
         content=[
             {"type": "text", "text": "describe the weather in this image"},
@@ -750,7 +750,7 @@ def test_image_token_counting_png() -> None:
     actual = model.get_num_tokens_from_messages([message])
     assert expected == actual
 
-    image_data = base64.b64encode(httpx.get(image_url).content).decode("utf-8")
+    image_data = base64.b64encode(httpx.get(image_url, timeout=10.0).content).decode("utf-8")
     message = HumanMessage(
         content=[
             {"type": "text", "text": "how many dice are in this image"},
diff --git a/libs/partners/openai/tests/integration_tests/chat_models/test_base_standard.py b/libs/partners/openai/tests/integration_tests/chat_models/test_base_standard.py
index c49d5a40e1f..c572a850b6b 100644
--- a/libs/partners/openai/tests/integration_tests/chat_models/test_base_standard.py
+++ b/libs/partners/openai/tests/integration_tests/chat_models/test_base_standard.py
@@ -92,7 +92,7 @@ class TestOpenAIStandard(ChatModelIntegrationTests):
     def test_openai_pdf_inputs(self, model: BaseChatModel) -> None:
         """Test that the model can process PDF inputs."""
         url = "https://www.w3.org/WAI/ER/tests/xhtml/testfiles/resources/pdf/dummy.pdf"
-        pdf_data = base64.b64encode(httpx.get(url).content).decode("utf-8")
+        pdf_data = base64.b64encode(httpx.get(url, timeout=10.0).content).decode("utf-8")
 
         message = HumanMessage(
             [
diff --git a/libs/partners/openai/tests/integration_tests/chat_models/test_responses_standard.py b/libs/partners/openai/tests/integration_tests/chat_models/test_responses_standard.py
index a2b63e1ab8c..37466928ab1 100644
--- a/libs/partners/openai/tests/integration_tests/chat_models/test_responses_standard.py
+++ b/libs/partners/openai/tests/integration_tests/chat_models/test_responses_standard.py
@@ -87,7 +87,7 @@ class TestOpenAIResponses(TestOpenAIStandard):
     def test_openai_pdf_tool_messages(self, model: BaseChatModel) -> None:
         """Test that the model can process PDF inputs in `ToolMessage` objects."""
         url = "https://www.w3.org/WAI/ER/tests/xhtml/testfiles/resources/pdf/dummy.pdf"
-        pdf_data = base64.b64encode(httpx.get(url).content).decode("utf-8")
+        pdf_data = base64.b64encode(httpx.get(url, timeout=10.0).content).decode("utf-8")
 
         tool_message = ToolMessage(
             content_blocks=[
diff --git a/libs/standard-tests/langchain_tests/integration_tests/chat_models.py b/libs/standard-tests/langchain_tests/integration_tests/chat_models.py
index f014e37aae3..9191fd61d5a 100644
--- a/libs/standard-tests/langchain_tests/integration_tests/chat_models.py
+++ b/libs/standard-tests/langchain_tests/integration_tests/chat_models.py
@@ -151,7 +151,7 @@ def _get_base64_from_url(url: str) -> str:
         )
         warnings.warn(warning_message, stacklevel=2)
     headers = {"User-Agent": user_agent} if user_agent else {}
-    httpx_response = httpx.get(url, headers=headers).content
+    httpx_response = httpx.get(url, headers=headers, timeout=10.0).content
     return base64.b64encode(httpx_response).decode("utf-8")
 
 
@@ -2583,7 +2583,7 @@ class ChatModelIntegrationTests(ChatModelTests):
             pytest.skip("Model does not support PDF inputs.")
 
         url = "https://www.w3.org/WAI/ER/tests/xhtml/testfiles/resources/pdf/dummy.pdf"
-        pdf_data = base64.b64encode(httpx.get(url).content).decode("utf-8")
+        pdf_data = base64.b64encode(httpx.get(url, timeout=10.0).content).decode("utf-8")
 
         message = HumanMessage(
             [
@@ -2781,7 +2781,7 @@ class ChatModelIntegrationTests(ChatModelTests):
             pytest.skip("Model does not support image message.")
 
         image_url = "https://raw.githubusercontent.com/langchain-ai/docs/4d11d08b6b0e210bd456943f7a22febbd168b543/src/images/agentic-rag-output.png"
-        image_data = base64.b64encode(httpx.get(image_url).content).decode("utf-8")
+        image_data = base64.b64encode(httpx.get(image_url, timeout=10.0).content).decode("utf-8")
 
         # OpenAI CC format, base64 data
         message = HumanMessage(
@@ -2887,7 +2887,7 @@ class ChatModelIntegrationTests(ChatModelTests):
             pytest.skip("Model does not support image tool message.")
 
         image_url = "https://raw.githubusercontent.com/langchain-ai/docs/4d11d08b6b0e210bd456943f7a22febbd168b543/src/images/agentic-rag-output.png"
-        image_data = base64.b64encode(httpx.get(image_url).content).decode("utf-8")
+        image_data = base64.b64encode(httpx.get(image_url, timeout=10.0).content).decode("utf-8")
 
         # OpenAI CC format, base64 data
         oai_format_message = ToolMessage(
@@ -2986,7 +2986,7 @@ class ChatModelIntegrationTests(ChatModelTests):
             pytest.skip("Model does not support PDF tool message.")
 
         url = "https://www.w3.org/WAI/ER/tests/xhtml/testfiles/resources/pdf/dummy.pdf"
-        pdf_data = base64.b64encode(httpx.get(url).content).decode("utf-8")
+        pdf_data = base64.b64encode(httpx.get(url, timeout=10.0).content).decode("utf-8")
 
         tool_message = ToolMessage(
             content_blocks=[
@@ -3122,7 +3122,7 @@ class ChatModelIntegrationTests(ChatModelTests):
         ]
         if self.supports_image_inputs:
             image_url = "https://raw.githubusercontent.com/langchain-ai/docs/4d11d08b6b0e210bd456943f7a22febbd168b543/src/images/agentic-rag-output.png"
-            image_data = base64.b64encode(httpx.get(image_url).content).decode("utf-8")
+            image_data = base64.b64encode(httpx.get(image_url, timeout=10.0).content).decode("utf-8")
             human_content.append(
                 {
                     "type": "image",
diff --git a/libs/text-splitters/langchain_text_splitters/base.py b/libs/text-splitters/langchain_text_splitters/base.py
index 19114b253df..fa94ee2d464 100644
--- a/libs/text-splitters/langchain_text_splitters/base.py
+++ b/libs/text-splitters/langchain_text_splitters/base.py
@@ -227,7 +227,7 @@ class TextSplitter(BaseDocumentTransformer, ABC):
         cls,
         encoding_name: str = "gpt2",
         model_name: str | None = None,
-        allowed_special: Literal["all"] | AbstractSet[str] = set(),
+        allowed_special: Literal["all"] | AbstractSet[str] = None,
         disallowed_special: Literal["all"] | Collection[str] = "all",
         **kwargs: Any,
     ) -> Self:
@@ -247,6 +247,8 @@ class TextSplitter(BaseDocumentTransformer, ABC):
         Raises:
             ImportError: If the tiktoken package is not installed.
         """
+        if allowed_special is None:
+            allowed_special = set()
         if not _HAS_TIKTOKEN:
             msg = (
                 "Could not import tiktoken python package. "
@@ -302,7 +304,7 @@ class TokenTextSplitter(TextSplitter):
         self,
         encoding_name: str = "gpt2",
         model_name: str | None = None,
-        allowed_special: Literal["all"] | AbstractSet[str] = set(),
+        allowed_special: Literal["all"] | AbstractSet[str] = None,
         disallowed_special: Literal["all"] | Collection[str] = "all",
         **kwargs: Any,
     ) -> None:
@@ -319,6 +321,8 @@ class TokenTextSplitter(TextSplitter):
         Raises:
             ImportError: If the tiktoken package is not installed.
         """
+        if allowed_special is None:
+            allowed_special = set()
         super().__init__(**kwargs)
         if not _HAS_TIKTOKEN:
             msg = (