Nuxtjs Guideline: DataFetching — Use transform for data manipulation. Description: Transform data before storing in state. Do: transform option for data shaping. Don't: Manual transformation after fetch. Good Example: useFetch('/api/posts', { transform: (posts) => posts.map(p => p.title) }). Bad Example: const titles = data.value.map(p => p.title). Severity: Low. Docs: https://nuxt.com/docs/api/composables/use-fetch.