How are validate GraphQL documents inside Phoenix controllers

I have GQL controller like this

@entity_fragment """
  fragment userFields on User {
@graphql \"""
    query ($filter: UserFilter) {
      users(filter: $filter, limit: 10){
  def index(conn, %{data: data}) do
    render conn, "index.html", data

But my schema fields are in snake_case( :address_email).
I’m wrong if i say this fragment query should never pass validation ( addressEmail is camelCase in the entity_fragment but snake_case in schema).