Kernel Function ChatHistory not passing?

[mholland10]

I'm currently running into a problem with the semantic kernel auto function choice behavior in python where once I specify that a value needs to be passed along into my function, the system will delete it. Weirdly this happens to any kernel argument that isn't the user_input, that seems to remain the same for some reason.
Here's a first screen shot of the ChatHistory metadata for the tool call where you can see that the history field does in fact exist and is populated:

Here's a second screen shot of when I specify that history needs to be passed along of it being overwritten with an empty dict:

The only difference between these two pictures is that in the first one I have the function as async def get_negotiation_message(self, user_input: str) -> str: and the second one is async def get_negotiation_message(self, user_input: str, history) -> str:

[moonbox3]

Hi @mholland10, thanks for your question. We can do a better job of documenting this (I will file an issue to update our documentation and even provide a sample if that is helpful, too). We have some "reserved" function parameter names like kernel and arguments which will allow a user to use these specific complex objects as part of function calling.

So if I have the following code:

class SimplePlugin:
    @kernel_function(name="GetWeather", description="Get the weather for a location.")
    async def get_the_weather(self, location: str, arguments: KernelArguments) -> str:
        return f"Received user input: {location}, the weather is nice!"

The arguments kernel function parameter will later allow us to extract those specific kernel arguments passed into either the kernel.invoke() or the chat_service.get_chat_message_contents() methods:

We can see the location is populated and the chat_history exists as part of the KernelArguments. Apologies that this isn't super obvious, but as I mentioned above, we'll work to improve docs/samples.

If you're really keen to understand where this happens, it's in the following method called gather_function_parameters. Reserved parameter names include: kernel, service, execution_settings, and arguments.

As a note: the reason why your history was coming back blank is because history was looked at as a new parameter, unrelated to the kernel arguments. And when we find that the underlying type is of ChatHistory, the model is sending back something like {"messages": []} and we then instantiate the ChatHistory with a new message list.

[moonbox3]

Tracking docs/samples improvements as part of #10215.

[mholland10]

Ah, that makes sense, thanks for the reply!