Error 500 in graphql-yoga serveless deploy in vercel

Question

I have a basic graphql-yoga server in port 4001,and i try to deploy to vercel serveless, but i have allways these error:

This Serverless Function has crashed.

Your connection is working correctly.

Vercel is working correctly.

500: INTERNAL_SERVER_ERROR
Code: FUNCTION_INVOCATION_FAILED
ID: iad1::qs77w-1671197012548-43a160e0d3fb

These is my vercel config:

{
"version": 2,
"builds": [
  { 
    "src": "index.js", 
    "use": "@now/node"
  }
],
"routes": [
    { "src": "/(.*)", "dest": "index.js" }
  ]
}