class City {
    public function __construct(
        public string $name,
        public int $population,
        public string $country,
        public string $mayor,
    ) {
    }
}

$city = new City('Berlin');
$messages = new MessageBag(
    Message::ofUser('Please research the missing data attributes for this city', $city),
);
$result = $platform->invoke($messages, [
    'response_format' => $city,
]);

dump($result->asObject());
// City('Berlin', 3500000, 'Germany', 'Kai Wegner')