Always mention pagination, proper status codes, and a consistent error format - these show production awareness.
Strong answers cover CRUD endpoints with proper HTTP verbs (GET, POST, PUT/PATCH, DELETE), meaningful status codes (200, 201, 404, 422), pagination for list endpoints, consistent error response format, and versioning strategy. Bonus: mention idempotency and rate limiting.
Tests fundamental web development knowledge. Even juniors should know basic REST conventions. Mid/seniors should discuss pagination, filtering, and error standardisation.