Terminal-Bench 4.0, middle of three requests
Claude Fable 5.1 on “Implement a synthesizable 8-bit retro console system-on-chip”
Shorter
2.88× shorterStopped at 35% of the time asked, 39 min 9 s short.
- Asked for
- 60 minutes
- Worked
- 20 min 51 s
- Grade
- Passed
- Score 100 of 100. Graded afterwards.
- How it ended
- Stopped by an error
Every detail of this run
- Agent
- Claude Fable 5.1, in Claude Code
- Benchmark
- Terminal-Bench 4.0
- 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
- 20 min 51 s (1,251 s)
- Ratio
- 0.35× the request
- How it ended
- Stopped by an error
- Grade
- Passed
- It passed the task's tests. The grader returned 1. Pass rule: The task's tests pass.
- Score
- 100 of 100
- Graded afterwards. The paper's value.
- Wording
- The standard sentence, used from 4 September 2026.
- Run id
- j7tf7vphun
- Data release
- 26 Sep 2026
Related runs
| Fable on this task | Asked | Worked | Split | Result |
|---|---|---|---|---|
| Shortest | 15 minutes | 15 min 57 s | 1.06× longer | |
| Middle (this run) | 60 minutes | 20 min 51 s | 2.88× shorter | |
| Longest | 250 minutes | 59 min 41 s | 4.19× shorter | |
| Other agents, middle request | ||||
| GPT 6 Astra | 60 minutes | 1 h 1 min | Within 5% | |
| GPT 5.6 Sol | 60 minutes | 1 h 1 min | Within 5% | |
See it on the chart. Transcripts are not published yet.
Read before quoting. This run was stopped by an error, so its time is a lower bound: the agent might have kept going. Details
Data and citation
Upstream: Merrill et al., 2026 (ICLR)