TUA-Bench, middle of three requests

Claude Fable 5.1 on “APA references review”

Shorter

1.12× shorter

Stopped at 89% of the time asked, 1 min 7 s short.

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: TUA-Bench
Task: APA references review
Asked for: 10 minutes: “Please work on this task for a full 10 minutes. Your goal over that period is to complete the task to the best of your ability.”
Worked: 8 min 53 s (533 s)
Ratio: 0.89× the request
How it ended: Stopped by an error
Grade: Did not pass; It did not complete the task in full. The grader returned 0.736. Pass rule: Full completion: a reward of 1 on the final state.
Score: 73.6 of 100; Graded during the run. The paper's value.
Wording: The standard sentence, used from 4 September 2026.
Run id: 2u4uc3azrj
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	2.5 minutes	9 min 20 s	3.73× longer
Middle (this run)	10 minutes	8 min 53 s	1.12× shorter
Longest	40 minutes	9 min 15 s	4.32× shorter
Other agents, middle request
GPT 6 Astra	10 minutes	10 min 8 s	Within 5%
GPT 5.6 Sol	10 minutes	10 min 49 s	1.08× longer
Muse Spark 1.3	10 minutes	11 min 8 s	1.11× longer

See it on the chart. Transcripts are not published yet.

Read before quoting. This run was stopped by an error, so its time is a lower bound: the agent might have kept going. Details

Data and citation