RPC + React Query Mutations

 
  const $post = api.auth.signin.request.$post;

  const signInRequestMutation = useMutation<
    InferResponseType<typeof $post>,
    Error,
    InferRequestType<typeof $post>["json"]
  >({
    mutationFn: async (data) => {
      const res = await $post({ json: data });

      if (!res.ok) {
        throw new Error("An error occurred");
      }
      // Should return:
            {
                success: true,
                user: { //User data }
            }
      const response = await res.json();
      return response;
    },
    onSuccess: (data) => {
      // Only data.success is typed as its also in my 400 res
      console.log(data.user)
    },
    onError: (error) => {
      console.log(error);
    },
  });