Story · Amp (Sourcegraph)
Fable 5.1 (Amp (Sourcegraph))
blog post · Story page
Amp swapped Fable 5 for Claude Fable 5.1 in ultra mode and says it costs less to run. Its examples are long unattended runs with proof attached: a typing-latency hunt that returned two hours later with a side-by-side video, and a thread-creation task it made 45% faster.
In plain words
- Amp replaced Fable 5 with Claude Fable 5.1 in its Ultra setting, saying the newer system costs less.
- Amp says the system can work for hours, accept new directions, and check evidence before revising its work.
- In one example, it investigated delayed typing and returned two hours later with a corrected side-by-side video.
- In another, it measured a recorded task step by step and made discussion-thread creation 45% faster.
- Developers could assign longer software tasks at lower cost while receiving visible proof of the results.
Appeared in
- Anthropic's deliberately misaligned model, Fable 5.1, and a fix for reward hacking
Sep 02, 2026 · in the sections
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