Is the `.inputValidator` on server functions only meant to be used for type validation?

import { createFileRoute, Link } from '@tanstack/react-router'
import { createServerFn } from '@tanstack/react-start'
import { FormEvent } from 'react'
import { z, ZodError } from 'zod'

const AuthUserSchema = z.object({
  email: z.email(`Email is not valid`).min(1, `Email is required`),
  password: z.string().min(1, `Password is required`)
    .min(5, `Password must be at least 5 characters`),
});

const submitForm = createServerFn({ method: 'POST' })
  .inputValidator(AuthUserSchema)
  .handler(async({ data }) => {
    const email = data.email
    const password = data.password

    console.log({ email, password })

    // Process the form...
    return { success: true }
  })

export const Route = createFileRoute('/auth/signin')({
  component: RouteComponent,
})

function RouteComponent() {
  const handleSubmit = async (e: FormEvent<HTMLFormElement>) => {
    e.preventDefault()
    const formData = new FormData(e.currentTarget)

    const email = formData.get("email") as string;
    const password = formData.get("password") as string;

    try {
      await submitForm({ data: { email, password }})
    } catch (error) {
      // Handle Zod validation errors
      console.log('Error caught:', error) // Debug log
      console.log('Error type:', error?.message) // Debug log
      console.log('Error data:', error?.data) // Debug log
    }
  }

  return (
    <div className="w-11/12 p-12 px-6 py-10 rounded-lg sm:w-8/12 md:w-6/12 lg:w-5/12 2xl:w-3/12 sm:px-10 sm:py-6">
      <h2 className="font-semibold text-4xl mb-4">Sign in</h2>
      ... Form code would be here
    </div>
  )
}