Anthropic has officially retired the original Claude Sonnet 4 and Claude Opus 4 API model IDs as of June 15, 2026.
If you are using Claude in AI agents, n8n, Zapier, automations or custom applications, check whether your workflows still reference:
claude-sonnet-4-20250514
claude-opus-4-20250514
If they do, those API requests may no longer work.
Update to the new model IDs:
✅ claude-sonnet-4-6
✅ claude-opus-4-8
A small change but an important one if your automations rely on Claude.
Hope this saves someone a debugging session. 🙌