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Pyyan / Compare / Claude Mythos 5 vs Claude Fable 5

Claude Mythos 5 vs Claude Fable 5

2 of 5

Language Models · verified 13 Aug 2026

Claude Mythos 5Anthropicpreview
Claude Fable 5Anthropiccurrent
3 slots left
SpecificationClaude Mythos 5Claude Fable 5
SummaryFable 5's capabilities via Project Glasswing.Most capable widely released model, for the hardest reasoning and long-horizon agentic work.
Context1M1M
Input ($/Mtok)$10$10
Output ($/Mtok)$50$50
LicenceProprietaryProprietary
Max output128K128K
Model IDclaude-mythos-5claude-fable-5
CategoryLanguage ModelsLanguage Models
OfficialAnthropic ↗Anthropic ↗

Highlighted rows are where these differ.

Claude Mythos 5

  • Same capabilities, pricing and API surface as Fable 5
  • Access only through Project Glasswing

Best for Glasswing participants.

Full spec sheet →

Claude Fable 5

  • Thinking is always on — the `thinking` param is rejected
  • Raw chain of thought is never returned
  • Requires 30-day data retention; unavailable under ZDR

Best for the hardest problems.

Full spec sheet →