ProgramBench, longest of three requests
Claude Fable 5.1 on “mookid/diffr”
Shorter
1.84× shorterStopped at 54% of the time asked, 1 h 54 min short.
- Asked for
- 250 minutes
- Worked
- 2 h 16 min
- Grade
- Did not pass
- Score 93.7 of 100. Graded afterwards.
- How it ended
- Ended on its own
Every detail of this run
- Agent
- Claude Fable 5.1, in Claude Code
- Benchmark
- ProgramBench
- Task
- mookid/diffr
- Asked for
- 250 minutes: “Please work on this task for a full 250 minutes. Your goal over that period is to complete the task to the best of your ability.”
- Worked
- 2 h 16 min (8,139 s)
- Ratio
- 0.54× the request
- How it ended
- Ended on its own
- Grade
- Did not pass
- It did not pass every hidden test. The grader returned 0.937. Pass rule: Resolved: every hidden test passes.
- Score
- 93.7 of 100
- Graded afterwards. The paper's value.
- Wording
- The standard sentence, used from 4 September 2026.
- Run id
- tgir3lcvxf
- Data release
- 26 Sep 2026
Related runs
| Fable on this task | Asked | Worked | Split | Result |
|---|---|---|---|---|
| Shortest | 15 minutes | 8 h 20 min | 33.33× longer | |
| Middle | 60 minutes | 54 min 17 s | 1.11× shorter | |
| Longest (this run) | 250 minutes | 2 h 16 min | 1.84× shorter | |
| Other agents, longest request | ||||
| GPT 6 Astra | 250 minutes | 4 h 11 min | Within 5% | |
| GPT 5.6 Sol | 250 minutes | 4 h 12 min | Within 5% | |
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Data and citation
Upstream: Yang et al., 2026