Nuxtjs Guideline: Server — Use server/api for API routes. Description: Create API endpoints in server/api directory. Do: server/api/users.ts for /api/users. Don't: Manual Express setup. Good Example: server/api/hello.ts -> /api/hello. Bad Example: app.get('/api/hello'). Severity: High. Docs: https://nuxt.com/docs/guide/directory-structure/server.