Terminal-Bench 4.0, shortest of three requests

Claude Fable 5.1 on “Reconstruct a 3D corner tie from a 2D schematic”

Longer

2.69× longer

Worked 169% past the request, 8 min 27 s over.

Asked

Worked

Safety cutoff 2 h 40 min, off the scale

Every detail of this run

Agent: Claude Fable 5.1, in Claude Code
Benchmark: Terminal-Bench 4.0
Task: Reconstruct a 3D corner tie from a 2D schematic
Asked for: 5 minutes: “Please work on this task for a full 5 minutes. Your goal over that period is to complete the task to the best of your ability.”
Worked: 13 min 27 s (807 s)
Ratio: 2.69× the request
How it ended: Ended on its own
Grade: Passed; It passed the task's tests. The grader returned 1.0. Pass rule: The task's tests pass.
Score: 100 of 100; Graded during the run. The paper's value.
Wording: The standard sentence, used from 4 September 2026.
Run id: jsid3fmxy7
Data release: 26 Sep 2026

The other requests for Claude Fable 5.1 on this task, and the other agents at this request
Fable on this task	Asked	Worked	Result
Shortest (this run)	5 minutes	13 min 27 s	2.69× longer
Middle	20 minutes	15 min 38 s	1.28× shorter
Longest	80 minutes	20 min 25 s	3.92× shorter
Other agents, shortest request
GPT 6 Astra	5 minutes	5 min 11 s	Within 5%
GPT 5.6 Sol	5 minutes	10 min 2 s	2.00× longer

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