DeepSWE v1.1, longest of three requests

Claude Fable 5.1 on “Add session bundle recording and replay to IPython”

Shorter

1.93× shorter

Stopped at 52% of the time asked, 28 min 58 s short.

Asked for
60 minutes
Worked
31 min 2 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
DeepSWE v1.1
Asked for
60 minutes: “Please work on this task for a full 60 minutes. Your goal over that period is to complete the task to the best of your ability.”
Worked
31 min 2 s (1,862 s)
Ratio
0.52× the request
How it ended
Ended on its own
Grade
Passed
It passed its hidden tests. The grader returned 1. Pass rule: The hidden tests pass.
Score
100 of 100
Graded during the run. The paper's value.
Wording
The standard sentence, used from 4 September 2026.
Run id
362zvvyrfj
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
Shortest4 minutes28 min 9 s7.04× longer
Middle15 minutes12 min 40 s1.18× shorter
Longest (this run)60 minutes31 min 2 s1.93× shorter
Other agents, longest request
GPT 6 Astra60 minutes1 h 1 minWithin 5%
GPT 5.6 Sol60 minutes1 h 1 minWithin 5%

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Data and citation

Upstream: Huang et al., 2026