# Claude Fable 5.2 and Mythos 5.2: Anthropic's top models get cheaper at $8/$40 and up to 30% faster

Canonical: https://theagenticweekly.com/news/claude-fable-5-2-mythos-5-2 · Evidence: Reported · First seen: 2026-11-09 18:59 UTC · Source published: not stated by the source · Brief published: 2026-11-09 19:08 UTC · Updated: 2026-11-09 19:08 UTC · Author: Agentic Weekly

> Claude Fable 5.2 is Anthropic's most capable generally available model, released Nov 9, 2026 as claude-fable-5-2 at $8 per million input tokens and $40 per million output tokens, down from Fable 5.1's $10/$50. Claude Mythos 5.2 is the same underlying model with lighter cyber and biology safeguards, available only through Anthropic's verification programs.

Models in this brief: [Claude Fable 5.2](https://theagenticweekly.com/models/claude-fable-5-2), [Gemini 4 Carbon](https://theagenticweekly.com/models/gemini-4-carbon), [Claude Opus 5.5](https://theagenticweekly.com/models/claude-opus-5-5)

## What changed

- Anthropic released Claude Fable 5.2 (API ID claude-fable-5-2) and Claude Mythos 5.2, which it says are the same underlying model; Fable carries stronger cyber and biology safeguards and is open to all users, while Mythos needs a Cyber or Life Sciences Verification Program approval.
- Price drops to $8 per million input tokens and $40 per million output tokens, and Anthropic says outputs come up to 30% faster than Fable 5.1 and Mythos 5.1; an optional fast mode generates tokens up to 2.5 times faster for $16/$80.
- The models overview lists a 1M-token context window, 128K max output tokens, always-on adaptive thinking with a default effort of high, a June 2026 knowledge cutoff and retirement not sooner than November 9, 2027.
- In Anthropic's table Fable 5.2 scores 49.1% on FrontierCode 2.0 at Xhigh effort versus 45.5% for Opus 5.5 and 42.8% for GPT-6 Astra, and 69.9% on FrontierSWE v2 versus 62.3% for Opus 5.5; Gemini 4 Carbon leads AutomationBench at 53.9% to Fable's 51.4%.
- Anthropic still recommends starting with Claude Opus 5.5 for most coding and knowledge work, and says Fable 5.2 can act as an Advisor that smaller Claude models consult or an Orchestrator that delegates to them.
- It is available today on all platforms including AWS, Google Cloud and Microsoft Azure; fast mode runs in Claude Code, the Claude Platform, Google Cloud and Microsoft Foundry, and preserved thinking now applies to all accounts.

## Who it matters for

Teams already paying for Fable 5.1 get a cheaper, faster drop-in upgrade by switching the model ID to claude-fable-5-2. Builders of long-running coding agents and orchestrators that hand work to Sonnet or Haiku are the main audience; Anthropic itself says most daily coding should start on Opus 5.5.

Security and life-sciences teams that need fewer refusals should look at Mythos 5.2 through the verification programs. Enterprises with zero data retention can ask about Enterprise Frontier Safeguards, which Anthropic says is in private beta; other customers get 30-day retention for safety monitoring.

## In the source's words

> "Claude Fable and Claude Mythos are the same underlying model."
> (Anthropic, Introducing Claude Fable 5.2 and Claude Mythos 5.2, https://www.anthropic.com/claude-fable-and-mythos-5-2)

> "Fast mode is available for $16 per million input tokens and $80 per million output tokens."
> (Anthropic, Introducing Claude Fable 5.2 and Claude Mythos 5.2, https://www.anthropic.com/claude-fable-and-mythos-5-2)

## What we have not verified

- We did not run this release ourselves.
- All benchmark scores are Anthropic's own reporting; several (including RoboDojo Sim) were run internally, and methodology is in the system card, which we did not read in full.
- The announcement gives a date but no publish time, so the source time is left blank; our watcher first saw the model in Anthropic's Electronics Design research post and in the anthropic Python SDK v2.7.0 release, which added claude-fable-5-2 and claude-mythos-5-2.
- We did not check the launch promotion details for paid Claude plans or regional availability of fast mode.

## Timeline

- Source published: not stated by the source
- First seen by our watcher: 2026-11-09 18:59 UTC (via Anthropic (news, research, engineering))
- Brief published: 2026-11-09 19:08 UTC

## Sources

- [Anthropic: Introducing Claude Fable 5.2 and Claude Mythos 5.2](https://www.anthropic.com/claude-fable-and-mythos-5-2) (primary source) (fetched 2026-11-09)
- [Claude docs: Models overview](https://platform.claude.com/docs/en/about-claude/models/overview) (primary source) (fetched 2026-11-09)
- [anthropic-sdk-python v2.7.0 release notes (GitHub)](https://github.com/anthropics/anthropic-sdk-python/releases/tag/v2.7.0) (primary source) (fetched 2026-11-09)

## Related

- [Claude Fable 5.2: specs, price and alternatives](https://theagenticweekly.com/models/claude-fable-5-2)
- [Gemini 4 Carbon: specs, price and alternatives](https://theagenticweekly.com/models/gemini-4-carbon)
- [Claude Opus 5.5: specs, price and alternatives](https://theagenticweekly.com/models/claude-opus-5-5)
- [All news briefs](https://theagenticweekly.com/news)
- [This week's releases](https://theagenticweekly.com/this-week)
- [New AI models this week](https://theagenticweekly.com/models/this-week)
- [AI model releases by month](https://theagenticweekly.com/models/releases)
- [Best LLM for coding](https://theagenticweekly.com/best/llm-for-coding)

## How to cite

Agentic Weekly, "Claude Fable 5.2 and Mythos 5.2: Anthropic's top models get cheaper at $8/$40 and up to 30% faster", published 2026-11-09 19:08 UTC, https://theagenticweekly.com/news/claude-fable-5-2-mythos-5-2