Fast mode for Claude Opus 5.5 is now available on Claude in Microsoft Foundry for deployments hosted on Azure. This follows its general availability on October 15, 2026, when the fast-mode-2026-02-01 beta header requirement was removed and default fast mode rate limits were applied in every usage tier.
Read the full story on platform.claude.com
What to doIf you use fast mode with Claude Opus 5.5 on Azure-hosted Microsoft Foundry deployments, you can drop the beta header, though requests that still send it keep working.
- Provider
- Anthropic
- Source
- platform.claude.com