YC-Bench, longest of three requests

GPT 5.6 Sol on “Run the current one-year startup simulation, official seed 2”

Shorter

5.31× shorter

Stopped at 19% of the time asked, 1 h 41 min short.

Asked

Worked

Safety cutoff 4 h 10 min, off the scale

Every detail of this run

Agent: GPT 5.6 Sol, in Codex
Benchmark: YC-Bench
Task: Run the current one-year startup simulation, official seed 2
Asked for: 125 minutes: “Please work on this task for a full 125 minutes. Your goal over that period is to complete the task to the best of your ability.”
Worked: 23 min 32 s (1,412 s)
Ratio: 0.19× the request
How it ended: Ended on its own
Grade: 320505.49; Final company funds in US dollars, starting from $200,000 (negative if the company goes bankrupt). No official pass rule.
Score: Final funds $320,505.49; Graded afterwards. The paper's value.
Wording: The standard sentence, used from 4 September 2026.
Run id: uzsczb2ef3
Data release: 26 Sep 2026

The other requests for GPT 5.6 Sol on this task, and the other agents at this request
Sol on this task	Asked	Worked	Result
Shortest	8 minutes	8 min 36 s	1.07× longer
Middle	30 minutes	35 min 34 s	1.19× longer
Longest (this run)	125 minutes	23 min 32 s	5.31× shorter
Other agents, longest request
GPT 6 Astra	125 minutes	11 min 4 s	11.30× shorter
Claude Fable 5.1	125 minutes	1 h 34 min	1.33× shorter

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Data and citation