Model and API retirements

Within 30 days64Firm dates ahead558

64 within 30 days · 558 firm dates ahead

claude-mythos-5-1 retirement date and replacement

Claude API · Model · not sooner than Sep 1, 2027

Vendor page

Dates

Checked Nov 9, 2026 on Anthropic's page
Not sooner thanSep 1, 2027 (not sooner than)The earliest date the vendor gives for a current model; the real date is announced later.
ReplacementNone named
What it isclaude-mythos-5-1 stops answering on Claude API no sooner than Sep 1, 2027.
Sourceplatform.claude.com/docs/en/about-claude/model-deprecations

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