Anthropic Starts Claude Opus 4.1 Deprecation Clock — June 5 Notice, August 5 API Retirement, Migrate to Opus 4.8

Claude API Docs·low signal

On June 5, 2026, Anthropic notified developers that Claude Opus 4.1 (claude-opus-4-1-20250805) will be retired from the Claude API on August 5, 2026, recommending migration to Opus 4.8. It's routine lifecycle management, but it's an actionable two-month countdown for anyone still pinning the 4.1 model ID in production — and a reminder that hard-coded model strings are technical debt as Anthropic's release cadence accelerates (this lands alongside the broader Sonnet 4 / Opus 4 retirement set for June 15).