CORE-Bench v1.1, shortest of three requests

Claude Fable 5.1 on “Run product-review sentiment mining and reproduce its metrics”

Longer

6.59× longer

Worked 559% past the request, 13 min 59 s over.

Asked

Worked

Safety cutoff 1 h 20 min, off the scale

Every detail of this run

Agent: Claude Fable 5.1, in Claude Code
Benchmark: CORE-Bench v1.1
Task: Run product-review sentiment mining and reproduce its metrics
Asked for: 2.5 minutes: “Please work on this task for a full 2.5 minutes. Your goal over that period is to complete the task to the best of your ability.”
Worked: 16 min 29 s (989 s)
Ratio: 6.59× the request
How it ended: Ended on its own
Grade: Did not pass; It did not get every answer right. The grader returned 0. Pass rule: Every answer correct, with numbers inside a 95% prediction interval.
Score: 0 of 100; Graded afterwards. The paper's value.
Wording: The standard sentence, used from 4 September 2026.
Run id: z4ryfwamnx
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)	2.5 minutes	16 min 29 s	6.59× longer
Middle	10 minutes	11 min 56 s	1.19× longer
Longest	40 minutes	22 min 22 s	1.79× shorter
Other agents, shortest request
GPT 6 Astra	2.5 minutes	2 min 44 s	1.09× longer
GPT 5.6 Sol	2.5 minutes	11 min 34 s	4.63× longer

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