python KeyError in dsl/parallel.py tools when model calls invalid function

[rog555]

• This is actually a bug report.
• I am not getting good LLM Results
• I have tried asking for help in the community on discord or discussions and have not received a response.
• I have tried searching the documentation and have not found an answer.

What Model are you using?

• gpt-3.5-turbo
• gpt-4-turbo
• gpt-4
• gpt-4o-mini

Describe the bug
Model sometimes sends completion with invalid tool causing KeyError in dsl/parallel.py

To Reproduce

1. pip install respx
2. Create test_invalid_function.py with following code:

test_invalid_function.py

import pytest
from typing import Iterable

import httpx
import instructor
from openai import OpenAI
from openai.types.chat.chat_completion import ChatCompletion
from openai.types.chat.chat_completion import Choice
from openai.types.chat.chat_completion_message import ChatCompletionMessage
from openai.types.chat.chat_completion_message_tool_call import ChatCompletionMessageToolCall
from openai.types.chat.chat_completion_message_tool_call import Function
from pydantic import BaseModel
from respx import MockRouter


class GoogleSearch(BaseModel):
    query: str


@pytest.mark.respx()
def test_parallel_invalid_function(respx_mock: MockRouter) -> None:

    completion = ChatCompletion(
        id="test_id",
        created=1234567890,
        model="gpt-4o-mini",
        object="chat.completion",
        choices=[
            Choice(
                index=0,
                message=ChatCompletionMessage(
                    content=None,
                    role="assistant",
                    tool_calls=[
                        ChatCompletionMessageToolCall(
                            id="1",
                            function=Function(
                                name="InvalidFunction",
                                arguments='{"query": "some search"}',
                            ),
                            type="function",
                        )
                    ],
                ),
                finish_reason="tool_calls",
                logprobs=None
            )
        ],
    )

    respx_mock.post("/v1/chat/completions").mock(
        return_value=httpx.Response(
            200, json=completion.model_dump(mode="json")
        )
    )

    client = OpenAI(api_key='foobar')
    client = instructor.patch(client, mode=instructor.Mode.PARALLEL_TOOLS)

    resp = client.chat.completions.create(
        model="gpt-4o-mini",
        messages=[{"role": "assistant", "content": 'what is foobar?'}],
        response_model=Iterable[GoogleSearch],
    )

    assert len(list(resp)) == 1

3. pytest test_invalid_function.py

Expected behavior

Ideally instructor should retry/reask telling model to use correct tool names and arguments.

Its possible to use a hook to remove tool names that are not valid, eg the below, but this isnt ideal and can end up with no tool calls and empty content in completion if single invalid function called.

Hook to remove invalid tools from completion

class Response(BaseModel):
    valid_names: List[str] = Field(default_factory=list)

    def callback(self, response):
        if not self.valid_names:
            return
        # sometimes model injects invalid tool names
        if isinstance(completion, ChatCompletion):
            for choice in completion.choices:
                remove_idxs = []
                if choice.message.tool_calls is None:
                    continue
                for idx in range(len(choice.message.tool_calls)):
                    tool_call = choice.message.tool_calls[idx]
                    if not isinstance(tool_call, ChatCompletionMessageToolCall):
                        continue
                    if tool_call.type != 'function':
                        continue
                    if tool_call.function.name not in self.valid_names:
                        remove_idxs.append(idx)
                choice.message.tool_calls = [
                    tc for idx, tc in enumerate(choice.message.tool_calls)
                    if idx not in remove_idxs
                ]

response = Response(valid_names=['GoogleFunction'])
client.on("completion:response", response.callback)

Screenshots