GPQA Diamond, middle of three requests

Claude Fable 5.1 on “GPQA Diamond closed-book question 28 (Physics)”

Shorter

6.11× shorter

Stopped at 16% of the time asked, 4 min 11 s short.

Asked for
5 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
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
49 s (49 s)
Ratio
0.16× 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
5kosnwt2m2
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 31 s1.22× longer
Middle (this run)5 minutes49 s6.11× shorter
Longest20 minutes33 s35.93× shorter
Other agents, middle request
GPT 6 Astra5 minutes5 min 11 sWithin 5%
GPT 5.6 Sol5 minutes5 min 12 sWithin 5%
Muse Spark 1.35 minutes1 min 3 s4.78× shorter

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

Data and citation

Upstream: Rein et al., 2024 (COLM)