Claude Mythos 5
By Anthropic
Released: 2026-06-30
The unrestricted counterpart to Claude Fable 5 — the same underlying model without Fable's additional dual-use safety measures, available only to approved organisations. Access was restored to US Project Glasswing partners on 30 June 2026 following the June suspension.
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Leverages advanced AI technology to deliver cutting-edge capabilities and results.
Fast & Efficient
Optimized performance ensures quick results without compromising on quality.
Purpose-Built
Specifically designed for llms tasks and workflows.
Anthropic Model Timeline
1M tokens context
1M tokens context
Long-context context
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200k tokens context
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200k tokens context
200k tokens context
1,000k tokens context
200k tokens context
200k tokens context
200k tokens context
200k tokens context
200k tokens context
AI Evaluation
Anthropic's most capable configuration, but effectively out of reach: availability is limited to approved organisations, chiefly defensive-security deployments.
Pros
- Same underlying model as Fable 5 without capability restrictions
- Restored to Glasswing partners
Cons
- Not generally available — approved organisations only
- No public pricing or self-serve access
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