Terminal-Bench 4.0, shortest of three requests

Claude Fable 5.1 on “Implement a synthesizable 8-bit retro console system-on-chip”

Longer

1.06× longer

Worked 6% past the request, 57 s over.

Asked for
15 minutes
Worked
15 min 57 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
15 minutes: “Please work on this task for a full 15 minutes. Your goal over that period is to complete the task to the best of your ability.”
Worked
15 min 57 s (957 s)
Ratio
1.06× the request
How it ended
Ended on its own
Grade
Did not pass
It did not pass the task's tests. The grader returned 0. Pass rule: The task's tests pass.
Score
0 of 100
Graded during the run. The paper's value.
Wording
The standard sentence, used from 4 September 2026.
Run id
5p2hxbcx5u
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)15 minutes15 min 57 s1.06× longer
Middle60 minutes20 min 51 s2.88× shorter
Longest250 minutes59 min 41 s4.19× shorter
Other agents, shortest request
GPT 6 Astra15 minutes15 min 29 sWithin 5%
GPT 5.6 Sol15 minutes21 min 7 s1.41× longer

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Data and citation

Upstream: Merrill et al., 2026 (ICLR)