Anthropic Claude API
Retirement date set for claude-sonnet-4-5-20250929 on the API
Anthropic notified developers using Claude Sonnet 4.5 of its retirement on the Claude API. The retirement date is November 30, 2026, and the recommended replacement is claude-sonnet-5-5.
Affects: Developers calling claude-sonnet-4-5-20250929 on the Claude API