pydantic v2 - aggregate errors when using mix of native and custom types with Annotated

I have the following code:

from .consts import BASE_URL, HOSTNAME_PATTERN

class GenericParseException(Exception):
    pass

def validate_hostname(value: str) -> str:
    if value.startswith("http://") or value.startswith("https://"):
        raise GenericParseException("base_url should not include the protocol (http:// or https://)")

    if not re.match(HOSTNAME_PATTERN, value):
        raise GenericParseException("Invalid hostname format.")

    return value

HostnameType = Annotated[str, AfterValidator(validate_hostname)]


class Config(BaseModel):
    api_token: str
    base_url: HostnameType = BASE_URL

class ConfigParser:
    def __init__(self, logger: LoggerInterface):
        self.logger = logger
        
    def parse(self, config: dict[str, Any]) -> Config:
        errors: List[str] = []
        try:
            model = Config(**config)
            return model
        except ValidationError as e:
            errors.extend(e.errors())
        except GenericParseException as e:
            errors.append(f"Generic validation error: {e}")
        except Exception as e:
            errors.append(f"Unexpected error: {e}")
        finally:
            if errors:
                self.logger.error({
                    'action': 'validation',
                    'status': 'failed',
                    'errors': errors
                })
                raise ConfigParseException("; ".join(str(err) for err in errors))

I trying to aggregate the errors, without success... I've tried with both AfterValidator & BeforeValidator

The expected output should be something like:

api_token - required field
base_url - base_url should not include the protocol (http:// or https://)

I'm only getting the base_url error.

Any ideas?