Optional Parameter Input Becoming Required for Flow Submission

[prefectcboyd]

An Optional input that has a parameter requirement, is being coerced into a required field.

Below is a sample repo that demonstrates the issue - notably, if required_integer: int, is entirely removed (leaving only the Optional[InputModel], the custom deployment cannot be submitted. It can be submitted from the JSON page, however.

from typing import Optional

import prefect
from pydantic import BaseModel


class InputModel(BaseModel):
    required_field: int


@prefect.flow(name="test-flow")
def test(
    required_integer: int,
    optional_input_model: Optional[InputModel] = None,
) -> None:
    logger = prefect.get_run_logger()

    logger.info(f"{required_integer=}")
    logger.info(f"{optional_input_model=}")

[zhen0]

@prefectcboyd - since there is a workaround by using the json input, I'm marking as medium, please let me know if you think this needs a higher priority.