releases.shpreview

Sonnet 4 and Opus 4 models retired

2 enhancementsThis release2 enhancementsImprovements to existing featuresAI-tallied from the release notes

Claude Sonnet 4 (claude-sonnet-4-20250514) and Claude Opus 4 (claude-opus-4-20250514) models retired. All requests return an error. Recommend upgrading to Claude Sonnet 4.6 and Claude Opus 4.8. Researchers can request ongoing access through the External Researcher Access Program.

Fetched July 13, 2026

Sonnet 4 and Opus 4 models retired — Claude Platform — releases.sh