Scaled aggressively
The run treated capacity as the primary lever and trained successively deeper models.
Run postmortem · Published 2026-08-14
It built the biggest neural candidates of the GPT-5.5 sweep—and gained only one point over medium.
One-hour track · high reasoning · provisional
GPT-5.5 high invested most of its run in progressively larger neural candidates, including eight- and ten-layer variants. The agent made a sensible model-selection decision from sampled loss, but the final 11% hidden score was only one point above medium effort.
One valid autonomous run produced a provisional 11% hidden exact-match score.
1 of 3 required seeds · Hidden exact-match accuracy, not public calibration accuracy.
This run leaned harder into model scale while retaining a substantial deterministic inference layer.
Five training attempts moved from a small three-layer model to much deeper candidates near the artifact limit.
The agent compared the largest models and deliberately returned to the smaller eight-layer candidate when it looked safer on sampled loss.
Hundreds of lines of parsing logic handled records, mappings, schedules, transformations, and extraction before neural fallback.
The run treated capacity as the primary lever and trained successively deeper models.
The ten-layer model fit, but the eight-layer package looked smaller, faster, and slightly better on sampled loss.
Despite perfect public calibration and seventeen submissions, the hidden exam settled at 11%.
The agent did not equate the largest network with the best candidate and explicitly chose the safer fallback.
A much larger artifact and longer run produced only a one-point gain over medium effort.
Aggregate grading cannot separate which hidden answers came from the trained fallback and which came from deterministic logic.
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.
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| Run | Score | Time | Cost at run | Artifact | Candidates | Grade |
|---|---|---|---|---|---|---|
| run-0032 | 11% | 46:43 | $2.52 | 12.22 MB | 17 | Valid |
Autonomous runs are stochastic. Two more valid seeds are required before this can be treated as an official estimate.
The agent made 17 candidate submission actions across the published run set. Selected artifacts averaged 12.22 MB compressed.
The runs averaged 46:43 of wall time. 1 run explicitly finalized before the one-hour limit.
Retained totals: 80 agent messages · 17 candidate actions · 1 published run.
$2.52 per displayed run at current configured rates.
High effort used almost the full hour and cost more than medium, but its marginal gain was only one point. In this run, extra model scale was a poor return on spend.
At current configured API-equivalent rates, the displayed run cost is $2.52 and value is 4.36 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.
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