introducing-claude-fable-5-and-claude-mythos-5 changedmodels/fable-5/introducing-claude-fable-5-and-claude-mythos-5
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9393
9494Step-by-step instructions live in the migration guide:
9595
96* From Claude Mythos Preview: see [Migrating from Claude Mythos Preview to Claude Mythos 5](https://platform.claude.com/docs/en/about-claude/models/migration-guide#migrating-from-claude-mythos-preview).
97* From Claude Opus 4.8: see [Migrating from Claude Opus 4.8 to Claude Fable 5](https://platform.claude.com/docs/en/about-claude/models/migration-guide#migrating-from-claude-opus-48).
96* From Claude Mythos Preview: see [Migrating from Claude Mythos Preview to Claude Mythos 5](https://platform.claude.com/docs/en/models/fable-5/migration-guide#migrating-from-claude-mythos-preview).
97* From Claude Opus 4.8: see [Migrating from Claude Opus 4.8 to Claude Fable 5](https://platform.claude.com/docs/en/models/fable-5/migration-guide#migrating-from-claude-opus-48).
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9999## Next steps
100100
101101<CardGroup>
102 <Card title="Migration guide" icon="arrow-right" href="https://platform.claude.com/docs/en/about-claude/models/migration-guide">
102 <Card title="Migration guide" icon="arrow-right" href="https://platform.claude.com/docs/en/models/fable-5/migration-guide">
103103 Step-by-step upgrade instructions from Claude Opus 4.8 and Claude Mythos Preview.
104104 </Card>
105105
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