Claude Fable 5 vs Claude Opus

Use Fable 5 for hard, long-running work. Keep cheaper Claude models for short, bounded tasks.

Use Fable 5Ambitious codingLarge migrations, autonomous agents, multi-day project work, complex debugging.

Use Opus/Sonnet-class modelsRoutine workShort edits, summarization, extraction, copywriting, simple Q&A, first-pass drafts.

Decision rulePay for failure reductionFable 5 is worth it when a cheaper model's mistakes cost more than the token delta.