CLAUDE May 28, 2026

Claude Opus 4.8 Released — May 28, 2026

WHAT CHANGED

Anthropic released Claude Opus 4.8 on May 28, 2026 as an incremental upgrade to Opus 4.7. Performance gains across SWE-Bench Pro (69.2%), GDPval-AA (1890), OSWorld-Verified (83.4%). Same pricing as 4.7 ($5/$25 per million tokens). 1M context retained.

WHY IT MATTERS

After Fable 5 suspension on June 12, Opus 4.8 is now Anthropic's effective public flagship. Same pricing as 4.7 ($5/$25 per million tokens). For most workloads, this is now your daily driver — not the cheap option, but THE option. Fable 5's 1M context, agentic strength, and SWE-Bench leadership all rolled back to Opus 4.8 levels until access is restored.

HOW TO USE IT

Default API model string: claude-opus-4-8. Same input/output schemas as 4.7. Cost-sensitive workloads can drop to Sonnet 4.6 (1.7x cheaper) for routine traffic, Haiku 4.5 for classification. Avoid hard-coding claude-fable-5 anywhere — that string returns errors.

CLAUDE / TYPESCRIPT

const response = await anthropic.messages.create({
  model: "claude-opus-4-8",
  max_tokens: 8192,
  messages: [{ role: "user", content: prompt }]
});

claudeopus-4-8releaseanthropicmodel

ORIGINAL SOURCE

https://www.anthropic.com/news

VIEW ORIGINAL SOURCE →

After Fable 5’s June 12 suspension, Opus 4.8 is no longer the backup — it’s the frontline. Use claude-opus-4-8 as your default production model until Fable 5 access is restored. For cost-sensitive traffic, drop to Sonnet 4.6 (1.7x cheaper). For classification and routing, use Haiku 4.5. Do not hard-code claude-fable-5 anywhere in production.

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