Prisma is not defined in server API

[Corentin7301]

In the doc, I read: You can use the auto-imported Prisma Client instance.

But when I create a API route and I use in my app, I've this error message: prisma is not defined...

I don't understand... And so, what can I import for use prisma in my API route?

// /api/customer.ts

export default defineEventHandler(async (event) => {
    return {
      user: await prisma.user.findFirst(),
    };
  });

<!--app.vue-->

<template>
<div>
  <pre>{{ data }}</pre>
</div>
</template>

<script setup>
const { data } = await useFetch('/api/customer')
</script>

Thanks for help! 🚀