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nest_asyncio hangs AsyncAnthropic

Freshabout 21 hours ago
Mar 14, 20260 views
Confidence Score48%
48%

Problem

When running with `nest_asyncio.apply()` the AsyncAnthropic execution keeps staying in the thread [code block]

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1 Fix

Canonical Fix
Unverified Fix
New Fix – Awaiting Verification

Modify AsyncAnthropic Usage to Avoid nest_asyncio Conflict

Medium Risk

The `nest_asyncio.apply()` function modifies the event loop to allow nested async calls, which can create conflicts with certain libraries like AsyncAnthropic that may not expect or handle this modification properly. This can lead to the execution hanging as the library waits indefinitely for an event that never occurs due to the altered loop behavior.

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  1. 1

    Remove nest_asyncio.apply()

    Since nest_asyncio can cause compatibility issues with AsyncAnthropic, remove the call to nest_asyncio.apply() from your code. This will allow AsyncAnthropic to operate with the default event loop behavior.

    python
    import nest_asyncio

# Remove or comment out the following line:
# nest_asyncio.apply()
  2. 2

    Use asyncio.run() for Entry Point

    Ensure that your main async function is called using asyncio.run() instead of manually managing the event loop. This ensures proper handling of the event loop without modifications that could cause hangs.

    python
    import asyncio
from your_async_anthropic_module import main_async_function

if __name__ == '__main__':
    asyncio.run(main_async_function())
  3. 3

    Check for Blocking Calls

    Review your code for any blocking calls that might interfere with the async execution flow. Replace them with their async counterparts if available, or run them in a separate thread using asyncio.to_thread().

    python
    import asyncio

async def main():
    result = await asyncio.to_thread(blocking_function)
    # Continue with async logic
  4. 4

    Test with Minimal AsyncAnthropic Call

    Create a minimal test case that only calls AsyncAnthropic functionality to ensure that the issue is resolved. This helps isolate the problem and confirm that the library works without nest_asyncio.

    python
    import asyncio
from your_async_anthropic_module import call_anthropic_api

async def test_anthropic():
    response = await call_anthropic_api()
    print(response)

if __name__ == '__main__':
    asyncio.run(test_anthropic())

Validation

Run the modified code and ensure that the AsyncAnthropic calls complete successfully without hanging. Verify that the expected output is produced and that no errors related to event loop management are thrown.

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Environment

Submitted by

AC

Alex Chen

2450 rep

Tags

claudeanthropicllmapibug