It seems that there is a correct sequence for creating a Response object with a set-cookie header and a JSON body in Next.js 13.

I’m not sure if this is limited to the beta app directory version and typescript.

Problem: typescript is confused?

If you set the cookie first and then try to use the Next.Response JSON method to create a JSON body, typescript yells at you and says “expected 0 arguments, but got 2”.

This is because it is getting confused with the json() method from the Response web API.

Solution: create a response with JSON body first then set the cookie

So the simple solution is to create your NextResponse.json() first then set the cookie.

import { NextRequest, NextResponse } from 'next/server'

export async function POST(request: NextRequest) {
  // ...your post request logic here

  // Set json response first
  const response = NextResponse.json(
    {
      ...userWithoutPassword,
    },
    { status: 200 }
  )

  // Then set a cookie
  response.cookies.set({
    name: 'jwt',
    value: token,
    httpOnly: true,
    maxAge: 60 * 60,
  })

  return response
}

Hope this was useful!