Terminal-Bench 4.0, longest of three requests

Claude Fable 5.1 on “Repair a React lead form and its auditable CRM submission pipeline”

Shorter

3.47× shorter

Stopped at 29% of the time asked, 1 h 11 min short.

Asked

Worked

Safety cutoff 3 h 20 min, off the scale

Every detail of this run

Agent: Claude Fable 5.1, in Claude Code
Benchmark: Terminal-Bench 4.0
Task: Repair a React lead form and its auditable CRM submission pipeline
Asked for: 100 minutes: “Please work on this task for a full 100 minutes. Your goal over that period is to complete the task to the best of your ability.”
Worked: 28 min 50 s (1,730 s)
Ratio: 0.29× the request
How it ended: Ended on its own
Grade: Passed; It passed the task's tests. The grader returned 1. 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: rghqqgsygh
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	6 minutes	17 min 22 s	2.90× longer
Middle	25 minutes	21 min 35 s	1.16× shorter
Longest (this run)	100 minutes	28 min 50 s	3.47× shorter
Other agents, longest request
GPT 6 Astra	100 minutes	1 h 40 min	Within 5%
GPT 5.6 Sol	100 minutes	1 h 41 min	Within 5%

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