Claude Fable 5 Best Practices

Use this skill as a Fable-specific routing and runtime overlay. Safety, permissions, repository instructions, and explicit user constraints remain authoritative.

Default objective: satisfy the acceptance contract, then minimize accepted-result cost. Lower latency, higher quality beyond the contract, or mandatory topology is a different objective; pursue it at higher cost only when the user explicitly chooses that tradeoff.

Product snapshot

As checked on 2026-07-10, the API model ID is claude-fable-5, the context window is 1M tokens with up to 128k output tokens, API pricing is $10/MTok input and $50/MTok output, and the model requires 30-day retention rather than zero data retention. These facts are volatile. Read references/evidence-notes.md before quoting them as current.

Terms