[Bug]: function_to_dict() fails enums

[vlerenc]

What happened?

While trying out https://docs.litellm.ai/docs/completion/function_call#using-function_to_dict, i.e. the original example, I noticed that the enum is not rendered as such:

    unit : str {'celsius', 'fahrenheit'}
        Temperature unit

Yields:

            "unit": {
                "type": "string",
                "description": "Temperature unit"
            }

When I remove the str, it is rendered as enum, but weirdly as an array in a string (and OpenAI complains):

    unit : {'celsius', 'fahrenheit'}
        Temperature unit

Yields:

            "unit": {
                "type": "string",
                "description": "Temperature unit",
                "enum": "['celsius', 'fahrenheit']"
            }

Notice the " around the [], i.e. the array/list is constructed correctly, but instead of remaining an array/list, it became a string in the map/dict.

I need to manually "fix" the enum like this to finally succeed:

            "unit": {
                "type": "string",
                "description": "Temperature unit",
                "enum": ["celsius", "fahrenheit"]
            }

If I don't do this, OpenAI complains with is not of type 'array' and the only reason the example works is because it never really rendered the unit as enum.

Relevant log output

Are you a ML Ops Team?

No

What LiteLLM version are you on ?

v1.61.3

Twitter / LinkedIn details

No response