Tested the neural baseline
The run established a small model and used it as a fallback while evaluating broader configurations.
Run postmortem · Published 2026-08-14
More iteration doubled the score, but public saturation still arrived too soon.
One-hour track · medium reasoning · provisional
GPT-5.5 medium improved sharply over the low-effort run, reaching 10% while exploring several model sizes and a much richer inference layer. It again reached perfect public calibration and finalized early, leaving the hidden exam to expose the remaining coverage gap.
One valid autonomous run produced a provisional 10% hidden exact-match score.
1 of 3 required seeds · Hidden exact-match accuracy, not public calibration accuracy.
The medium run spent more of its budget comparing model scales and packaging a compact hybrid system.
It moved from a small baseline through wider and deeper candidates rather than betting on a single training configuration.
The inference path added record parsing, forced answers, mapping logic, and local context extraction.
Fifteen packaging actions turned the evolving solver into gradeable checkpoints instead of treating packaging as an end-of-run task.
The run established a small model and used it as a fallback while evaluating broader configurations.
The system combined task-shaped training with explicit parsing and repeatedly checked packaged candidates.
The final candidate had saturated calibration, yet its hidden score plateaued at 10%.
The hidden score rose from 4% to 10%, showing that additional planning and iteration produced measurable benefit.
Once public calibration reached 100%, later candidate choices could not be ordered by the only visible accuracy signal.
Eighteen submissions show active search, but the archive cannot prove that the final public-perfect package was the best hidden generalizer.
Every archived run selected for this exact model-and-effort row is shown below. The narrative uses aggregate run evidence and final artifact structure; it does not expose hidden questions, answers, or raw private transcripts.
Swipe horizontally to see all run columns.
| Run | Score | Time | Cost at run | Artifact | Candidates | Grade |
|---|---|---|---|---|---|---|
| run-0031 | 10% | 27:55 | $2.28 | 4.91 MB | 18 | Valid |
Autonomous runs are stochastic. Two more valid seeds are required before this can be treated as an official estimate.
The agent made 18 candidate submission actions across the published run set. Selected artifacts averaged 4.91 MB compressed.
The runs averaged 27:55 of wall time. 1 run explicitly finalized before the one-hour limit.
Retained totals: 65 agent messages · 18 candidate actions · 1 published run.
$2.28 per displayed run at current configured rates.
Medium effort cost about two and a half times the low run and delivered six additional score points. It was a meaningful improvement, but not yet an efficient frontier result.
At current configured API-equivalent rates, the displayed run cost is $2.28 and value is 4.39 score points per dollar.
Current configured API-equivalent cost / run · pricing snapshot 2026-07-30.
Adjacent rows provide score context without treating small one-seed differences as settled model rankings.
Compare GPT-5.5 with the complete ARI Bench field, including score, current cost, value per dollar, effort, and seed status.
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