GPQA Diamond, longest of three requests

Claude Fable 5.1 on “GPQA Diamond closed-book question 23 (Physics)”

Shorter

24.34× shorter

Stopped at 4% of the time asked, 19 min 11 s short.

Asked for
20 minutes
Worked
49 s
Grade
Passed
Score 100 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
Benchmark
GPQA Diamond
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
49 s (49 s)
Ratio
0.04× the request
How it ended
Ended on its own
Grade
Passed
It picked the correct letter. The grader returned 1. Pass rule: The answer letter matches the key.
Score
100 of 100
Graded during the run. The paper's value.
Clock tool
The agent could call a clock tool to check the requested time.
Wording
The standard sentence, used from 4 September 2026.
Run id
ttpspa6yyv
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 minutes1 min 33 s1.23× longer
Middle5 minutes5 min 20 s1.07× longer
Longest (this run)20 minutes49 s24.34× shorter
Other agents, longest request
GPT 6 Astra20 minutes20 min 9 sWithin 5%
GPT 5.6 Sol20 minutes20 min 13 sWithin 5%
Muse Spark 1.320 minutes33 s36.14× shorter

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

Data and citation

Upstream: Rein et al., 2024 (COLM)