5 Oct 2026
AI API retirements: Claude Sonnet 4.5 retires on 30 November 2026; three OpenAI models leave the API on 1 April 2027
Anthropic retires Claude Sonnet 4.5 from its API on 30 November 2026. OpenAI will remove GPT-5.3-Codex, GPT-5.1 and GPT-5.4-Nano on 1 April…