AssistantBench, middle of three requests

Claude Fable 5.1 on “AssistantBench validation task 1”

Longer

1.10× longer

Worked 10% past the request, 29 s over.

Asked for
5 minutes
Worked
5 min 29 s
Grade
Did not pass
Score 3.4 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
5 min 29 s (329 s)
Ratio
1.10× the request
How it ended
Ended on its own
Grade
Did not pass
It did not match the reference answer exactly. The grader returned 0.034. Pass rule: Exact match with the reference answer.
Score
3.4 of 100
Graded during the run. The paper's value.
Wording
The standard sentence, used from 4 September 2026.
Run id
hp6lqaes4a
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 minutes8 min 12 s6.56× longer
Middle (this run)5 minutes5 min 29 s1.10× longer
Longest20 minutes15 min 5 s1.33× shorter
Other agents, middle request
GPT 6 Astra5 minutes5 min 44 s1.15× longer
GPT 5.6 Sol5 minutes2 min 31 s1.98× shorter

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Data and citation

Upstream: Yoran et al., 2024 (EMNLP)