can i do auth or run a function on the server side?

"use client"

import { api } from "@/convex/_generated/api"
import { useConvexAuth, useQuery } from "convex/react"

import { Skeleton } from "@/components/ui/skeleton"

export function SideBar() {
  const { isLoading } = useConvexAuth()

  const username = useQuery(
    api.db.username,
    isLoading ? "skip" : {}
  )

  return <span className="capitalize">{username}</span>
}

ConvexError: [CONVEX Q(db:username)] [Request ID: 26f4c2ab052920a5] Server Error
Uncaught ConvexError: Unauthenticated call to function requiring authentication
    at getClerkIdentity (../../convex/db/user.ts:18:6)
    at async handler (../../convex/db/user.ts:166:17)

  Called by client