react-form-hook: useForm data not matching TypeScript type, but no errors

Question

I'm trying to validate a form using react-hook-form.

My code below is working fine, but as you can see Person.name is of type string; submitting the form results in

data = { name: 2 },

i.e. data.name is of type number. Why am I not getting a type error inside the onSubmit function? For me this was the whole point of using TypeScript in the first place...

Am I missing something, or do I really have register a (duplicate) validation method for my input (via useForm)?

Here is the piece of code that I would expect to break:

...
const onSubmit = (data: Person) => {
    console.log({ data });
};
...

---

Note that I'm setting valueAsNumber = true, see here useform/register; this is working properly as data.name is a number.

import { useForm } from "react-hook-form";


type Person = {
    name: string;
};

const PersonForm = () => {
    const { register, handleSubmit, formState: { errors } } = useForm<Person>();
    const onSubmit = (data: Person) => {
        console.log({ data });
    };

    console.log({ errors });

    return (
        <form onSubmit={handleSubmit(onSubmit)}>
            <div className="field">
                <label htmlFor="name">Name</label>
                <input
                    defaultValue="2"
                    type="text"
                    {...register("name", { required: true, valueAsNumber: true })}
                />
            </div>
            <button type="submit">Save</button>
        </form>
    );
};

<script src="https://cdnjs.cloudflare.com/ajax/libs/react/16.6.3/umd/react.production.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react-dom/16.6.3/umd/react-dom.production.min.js"></script>