Checked other resources

• This is a bug, not a usage question.
• I added a clear and descriptive title that summarizes this issue.
• I used the GitHub search to find a similar question and didn't find it.
• I am sure that this is a bug in LangChain rather than my code.
• The bug is not resolved by updating to the latest stable version of LangChain (or the specific integration package).
• This is not related to the langchain-community package.
• I posted a self-contained, minimal, reproducible example. A maintainer can copy it and run it AS IS.

Package (Required)

• langchain
• langchain-openai
• langchain-anthropic
• langchain-classic
• langchain-core
• langchain-model-profiles
• langchain-tests
• langchain-text-splitters
• langchain-chroma
• langchain-deepseek
• langchain-exa
• langchain-fireworks
• langchain-groq
• langchain-huggingface
• langchain-mistralai
• langchain-nomic
• langchain-ollama
• langchain-openrouter
• langchain-perplexity
• langchain-qdrant
• langchain-xai
• Other / not sure / general

Related Issues / PRs

No response

Reproduction Steps / Example Code (Python)

import asyncio
import gc
from langchain_openai.chat_models._client_utils import _AsyncHttpxClientWrapper

async def main():
    client = _AsyncHttpxClientWrapper(base_url="http://test", timeout=10)
    # used...
    pass

if __name__ == "__main__":
    asyncio.run(main()) 
    # Logic: loop is closed here
    gc.collect() # Trigger __del__ -> RuntimeError: no running event loop

Error Message and Stack Trace (if applicable)

Description

Description:

I found a resource cleanup issue in langchain-openai and langchain-anthropic.
The _AsyncHttpxClientWrapper.__del__ method attempts to schedule an async cleanup task using asyncio.get_running_loop().

However, if the object is garbage collected during interpreter shutdown or in a context where the event loop is already closed, get_running_loop() raises a RuntimeError.

The current code catches this in a broad except Exception: block and suppresses it, meaning self.aclose() is never called, potentially leading to unclosed resource warnings from httpx

Proposed Fix: Safely check for the running loop using try/except RuntimeError and loop.is_running() before attempting to schedule the cleanup task.

System Info

System Information

OS: Darwin
OS Version: Darwin Kernel Version 25.2.0: Tue Nov 18 21:08:48 PST 2025; root:xnu-12377.61.12~1/RELEASE_ARM64_T8132
Python Version: 3.13.0rc3 (v3.13.0rc3:fae84c70fbd, Oct 1 2024, 00:10:10) [Clang 15.0.0 (clang-1500.3.9.4)]

Package Information

langchain_core: 1.2.13
langsmith: 0.7.4
langgraph_sdk: 0.3.6

Other Dependencies

httpx: 0.28.1