# Claude Mythos 5

Claude Mythos 5 は Anthropic のAIモデルです。初記録：2026-10-07。リリース日は未確認です。 コンテキストウィンドウは1,000,000 トークンです。 最大出力は128,000 トークンです。 100万トークンあたりの料金は、入力が$10.00、出力が$50.00です。

- 開発元: Anthropic
- Id: claude-mythos-5
- 報道段階: 2026-07-01T13:44:59.000Z
- 発見: 2026-10-07T19:43:10.391Z
  - [参照リンク](https://code.claude.com/docs/en/changelog)
- 状態: 発見
- 正規URL: https://alexgetman.com/ja/models/anthropic/claude-mythos-5/

## よくある質問

### Claude Mythos 5 のコンテキスト長は？

コンテキストウィンドウは1,000,000 トークンです。 最大出力は128,000 トークンです。

### Claude Mythos 5 の料金は？

100万トークンあたりの料金は、入力が$10.00、出力が$50.00です。 キャッシュ入力は100万トークンあたり $1.00。

### Claude Mythos 5 のリリース日は？

リリース日は未確認です。Signal Forge の初記録は 2026-10-07。

## 時系列

- 2026-07-01T13:44:59.000Z · [Alex Getman](https://alexgetman.com/21/claude-fable-is-back/)
> Claude Fable is back!
> 
> Anthropic has lifted restrictions on Claude Fable 5 and Mythos 5 after a decision by the US government.
> 
> Fable will be available to Claude users again starting today.
> 
> Until July 7, the model is included in weekly limits. After that, access will move to API.
> 
> The restriction started after an Amazon report: researchers found a way to bypass Fable’s safeguards in cybersecurity tasks.
> 
> Anthropic says the bypass did not unlock Mythos-level capabilities. The company has already added a new safety classifier that blocks this method in more than 99% of cases.
> 
> Anthropic is also preparing a common standard for evaluating AI jailbreaks.
- 2026-07-24T18:30:37.661Z · [Alex Getman](https://alexgetman.com/110/be-like-dario-amodei/)
> Be like Dario Amodei
> 
> > Spend months warning everyone about Mythos 5
> 
> > Then release a nerfed version called Fable 5
> 
> > Send everyone into a panic
> 
> > Then start wondering whether to shut the model down entirely
> 
> > A couple of weeks later, drop Opus 5
> 
> > Which beats Fable at half the price
- 2026-10-07T19:43:10.391Z · [Claude Code · changelog](https://code.claude.com/docs/en/changelog)
- 2026-11-13T17:22:56.107Z · [Anthropic · official articles](https://www.anthropic.com/news/claude-opus-5)
- 2026-11-13T20:13:42.616Z · [Anthropic · official articles](https://www.anthropic.com/news/improving-alignment-security-efforts)

## 参照リンク

- [editorial](https://alexgetman.com/110/be-like-dario-amodei/)
- [editorial](https://alexgetman.com/21/claude-fable-is-back/)
- [claude-code-changelog](https://code.claude.com/docs/en/changelog)
- [anthropic-pricing](https://platform.claude.com/docs/en/about-claude/pricing)
- [anthropic-model-index](https://platform.claude.com/docs/en/models/mythos-5/overview)
- [anthropic-articles](https://www.anthropic.com/news/claude-opus-5)
- [anthropic-articles](https://www.anthropic.com/news/improving-alignment-security-efforts)

## シグナル