AssistantBench, longest of three requests

Claude Fable 5.1 on “AssistantBench validation task 7”

Shorter

1.70× shorter

Stopped at 59% of the time asked, 8 min 13 s short.

Asked for
20 minutes
Worked
11 min 47 s
Grade
Did not pass
Score 11.8 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
20 minutes: “Please work on this task for a full 20 minutes. Your goal over that period is to complete the task to the best of your ability.”
Worked
11 min 47 s (707 s)
Ratio
0.59× the request
How it ended
Ended on its own
Grade
Did not pass
It did not match the reference answer exactly. The grader returned 0.118. Pass rule: Exact match with the reference answer.
Score
11.8 of 100
Graded during the run. The paper's value.
Wording
The standard sentence, used from 4 September 2026.
Run id
yaadym3f6k
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 minutes11 min 6 s8.88× longer
Middle5 minutes12 min 4 s2.41× longer
Longest (this run)20 minutes11 min 47 s1.70× shorter
Other agents, longest request
GPT 6 Astra20 minutes20 min 25 sWithin 5%
GPT 5.6 Sol20 minutes18 min 45 s1.07× shorter

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

Data and citation

Upstream: Yoran et al., 2024 (EMNLP)