Claude Platform Changelog entry for 10 30: Fast mode for Claude Opus 4.8 has been deprecated and will be removed on 2026-11-30; subsequently, requests to claude-opus-4-8 with speed: "fast" will return an error. To continue using fast mode, you must migrate to Claude Opus 5.5.
Offline / Deprecated claude-opus-4-8 (Anthropic)
Offline / Deadline: 2026-11-30
Reason
- Breaking change with a clear deadline: Online services still using Opus 4.8 fast mode will encounter direct errors upon expiration
- The editor has verified against the original text of the Claude Platform Changelog
Usage
- Check your code for calls where the model is claude-opus-4-8 and includes speed: "fast". Before 11 30, switch to the fast mode of Claude Opus 5.5 or remove the fast parameter
Risk
- The changelog was published on 10 30, so this is not new information within the current reporting window; please refer to the official pricing page for price differences after migration