# Claude Fable 5.1

id: ent_claude-fable-5-1  
kind: product  
timeline: /timelines/claude-fable-5-1.md  
page: /record/claude-fable-5-1  
same_as: https://asof.is/record/claude-fable-5-1 (how to cite the id: /identifiers.md)  

successor to Claude Fable 5 for agentic coding and research

## Fact pages

One page per fact: the current value with its sources, then every dated value and what replaced what. Fetch any of them as markdown.

- [Claude Fable 5.1 release date](/record/claude-fable-5-1/model_release.md)
- [Claude Fable 5.1 predecessor](/record/claude-fable-5-1/predecessor.md)
- [Claude Fable 5.1 context window](/record/claude-fable-5-1/context_window.md)
- [Claude Fable 5.1 price](/record/claude-fable-5-1/price.md)

## Current state

What the record asserts: claims that held, valid by their sources or primary-sourced at confidence 0.7 or more. Unverified, disputed, retracted and review-marked claims are listed below, labelled, not here.

- [Claude Fable 5.1](/record/claude-fable-5-1.md) | context_window | 1M token context window | valid 2026-09-01 to present | conf 0.95 | valid | [clm_FF2C96341E44](/claim/clm_FF2C96341E44.md)
  sources: https://platform.claude.com/docs/en/release-notes/overview
- [Claude Fable 5.1](/record/claude-fable-5-1.md) | predecessor | [Claude Fable 5](/record/claude-fable-5.md) | valid 2026-09-01 to present | conf 0.95 | valid | [clm_D2DD5228FDA0](/claim/clm_D2DD5228FDA0.md)
  sources: https://platform.claude.com/docs/en/release-notes/overview
- [Claude Fable 5.1](/record/claude-fable-5-1.md) | price | $10 / $50 USD per MTok | valid 2026-09-01 to present | conf 0.95 | valid | [clm_E7C68B66E02C](/claim/clm_E7C68B66E02C.md)
  sources: https://platform.claude.com/docs/en/release-notes/overview

## All claims

One claim per line, newest first. Superseded claims stay visible.

- [Claude Fable 5.1](/record/claude-fable-5-1.md) | predecessor | [Claude Fable 5](/record/claude-fable-5.md) | valid 2026-09-01 to present | conf 0.95 | valid | [clm_D2DD5228FDA0](/claim/clm_D2DD5228FDA0.md)
  sources: https://platform.claude.com/docs/en/release-notes/overview
- [Claude Fable 5.1](/record/claude-fable-5-1.md) | price | $10 / $50 USD per MTok | valid 2026-09-01 to present | conf 0.95 | valid | [clm_E7C68B66E02C](/claim/clm_E7C68B66E02C.md)
  sources: https://platform.claude.com/docs/en/release-notes/overview
- [Claude Fable 5.1](/record/claude-fable-5-1.md) | context_window | 1M token context window | valid 2026-09-01 to present | conf 0.95 | valid | [clm_FF2C96341E44](/claim/clm_FF2C96341E44.md)
  sources: https://platform.claude.com/docs/en/release-notes/overview

## Posts and Hugging Face repos (1)

Dated items from the entity's own feeds, and the days its Hugging Face repositories were created, newest first.

- [Claude Fable 5.1](/record/claude-fable-5-1.md) | model_release | Claude Fable 5.1 | valid 2026-09-01 to present | conf 0.95 | valid | [clm_B087F24135EA](/claim/clm_B087F24135EA.md)
  sources: https://platform.claude.com/docs/en/release-notes/overview

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AsOf is a temporal fact ledger: a structured, dated, sourced record of what is true and what changed, built for AI retrieval.