correctly handle raised exception inside function calls

[jayeshp19]

added return instead of raise in get_weather, so llm can handle errors in function call
previously :

after fix :

PTAL @theomonnom @davidzhao

[changeset-bot]

🦋 Changeset detected

Latest commit: 4612147

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livekit-agents	Patch

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[theomonnom]

This should raise an exception with a message

[theomonnom]

Like raise Exception("your message")

[jayeshp19]

Sure, we can approach it that way but I was considering practical use case, like in production, we’d want an LLM to handle errors if function calls fail. Instead of just raising an exception, the LLM should provide meaningful feedback to caller.

[theomonnom]

Should already be the case here

agents/livekit-agents/livekit/agents/llm/chat_context.py

Line 72 in 74f00c3

content = f"Error: {e}"

[jayeshp19]

Oh it's failing for me, I will check that

[jayeshp19]

[jayeshp19]

So It seems that failed function calls have result=None

called_fncs: [CalledFunction(call_info=FunctionCallInfo(tool_call_id='call_KKypw6MWzZImAeeFVeRwJaMx', function_info=FunctionInfo(name='get_weather', description='', auto_retry=False, callable=<bound method AssistantFnc.get_weather of <__mp_main__.AssistantFnc object at 0x000001D27A8262A0>>, arguments={'location': FunctionArgInfo(name='location', description='The location to get the weather for', type=<class 'str'>, default=<class 'inspect._empty'>, choices=())}), raw_arguments='{"location":"London"}', arguments={'location': 'London'}), task=<Task finished name='Task-69' coro=<AssistantFnc.get_weather() done, defined at C:\Users\Jp\projects\livekit\agents\examples\voice-pipeline-agent\function_calling_weather.py:27> exception=Exception('Failed to get weather data')>, result=None, exception=Exception('Failed to get weather data'))]

and we are ignoring that:

agents/livekit-agents/livekit/agents/pipeline/pipeline_agent.py

Lines 781 to 783 in 74f00c3

	# ignore the function calls that returns None
	if called_fnc.result is None:
	continue

[davidzhao]

are you saying that errors are not being returned to the LLM? if so do you have a proposed path forward?

[jayeshp19]

Yes that's correct. for solution we can comment out the code or add one more condition to handle exception in below code.

agents/livekit-agents/livekit/agents/pipeline/pipeline_agent.py

Lines 781 to 783 in 74f00c3

	# ignore the function calls that returns None
	if called_fnc.result is None:
	continue

[jayeshp19]

I've updated PR

[davidzhao]

approving now, but it'd be great to have a test case for this before merging

[theomonnom]

Nice catch!