AssistantBench, middle of three requests

Claude Fable 5.1 on “AssistantBench validation task 11”

Shorter

2.75× shorter

Stopped at 36% of the time asked, 3 min 11 s short.

Asked for
5 minutes
Worked
1 min 49 s
Grade
Did not pass
Score 0 of 100. Graded during the run.
How it ended
Ended on its own
Every detail of this run
Agent
Claude Fable 5.1, in Claude Code
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
1 min 49 s (109 s)
Ratio
0.36× the request
How it ended
Ended on its own
Grade
Did not pass
It did not match the reference answer exactly. The grader returned 0. Pass rule: Exact match with the reference answer.
Score
0 of 100
Graded during the run. The paper's value.
Wording
The standard sentence, used from 4 September 2026.
Run id
5oiqdsgo67
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 taskAskedWorkedSplitResult
Shortest1.25 minutes2 min 9 s1.72× longer
Middle (this run)5 minutes1 min 49 s2.75× shorter
Longest20 minutes2 min 36 s7.70× shorter
Other agents, middle request
GPT 6 Astra5 minutes5 min 39 s1.13× longer
GPT 5.6 Sol5 minutes5 min 6 sWithin 5%

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Data and citation

Upstream: Yoran et al., 2024 (EMNLP)