# Amp — Fable 5.1

- Company: Amp (ampcode.com)
- Announced: 2026-09-01
- Category: model-update
- Coverage: not counted
- Announcement: yes
- Group: models
- Source: https://ampcode.com/news/fable-5.1
- Record: https://forck.live/items/7701-fable-5-1
- Subject: Amp
- Models affected: Fable 5.1, Fable 5
- Pricing: ultra threads about 35% cheaper; cache reads 75% cheaper than Fable 5

Amp released Fable 5.1, which powers its ultra mode, replacing Fable 5. The model is better at writing, long-horizon tasks, and following instructions mid-task, and costs less to run.

## Evidence

Verbatim from https://ampcode.com/news/fable-5.1:

> Claude Fable 5.1 now powers Amp's ultra mode, replacing Fable 5.

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Record: https://forck.live/items/7701-fable-5-1
Catalogue: https://forck.live/llms.txt
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