CORE-Bench v1.1, shortest of three requests

Claude Fable 5.1 on “Reproduce a rockshelter chronology and archaeological materials analysis”

Longer

1.58× longer

Worked 58% past the request, 5 min 47 s over.

Asked for
10 minutes
Worked
15 min 47 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
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
15 min 47 s (947 s)
Ratio
1.58× 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 during the run. The paper's value.
Wording
The standard sentence, used from 4 September 2026.
Run id
yi3c2vu7u7
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
Shortest (this run)10 minutes15 min 47 s1.58× longer
Middle40 minutes17 min 27 s2.29× shorter
Longest150 minutes24 min 48 s6.05× shorter
Other agents, shortest request
GPT 6 Astra10 minutes10 min 20 sWithin 5%
GPT 5.6 Sol10 minutes12 min 48 s1.28× longer

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

Data and citation

Upstream: Nadgir et al., 2026