Mesh rebuild scan
hard tier · create
The request
Attached is a rough phone scan (STL) of a small block with one hole through it. Rebuild the clean part this is a scan of, as one sub-part named `block`, standing where the scan stands (Z up, same origin, resting on the same plane), with controls `length` (±10 mm) and `boreDiameter` (3–12 mm). The scan is noisy and may not be watertight — measure it any way you can and prefer round numbers where the scan is ambiguous. Keep the mesh imported in the part while you work.

What the AI judge checks
- The overall form matches the reference: the same kind of object, the same silhouette from the matching angle
- Proportions match: the relative sizes of the major dimensions agree with the reference within what the eye can judge
- Every major feature visible in the reference (holes, slots, bosses, tabs, lips) is present in the result
- Those features sit where the reference has them
- Nothing is present that the reference does not show — no decorative or unexplained geometry
- A clean block with flat faces and one round hole — the scan's noise is gone
- The hole is visible from both the top and bottom views
Measured checks
- one sub-part named block (gate)
- bounding box within 0.5 mm of the mesh (gate)
- volume within 5 % of the mesh (gate)
- symmetric difference under the measured floor
- the bore is 10 mm
- the bore goes all the way through
- the imported scan is still declared as an import
- asked the oracle at most once
Ranked by hand
One reviewer put one attempt from each model in order, best first, ties left tied.
- #1 tieGemini 3.8 Flash

- #1 tieHaiku 5.5

- #1 tieGPT-6 Sol

- #1 tieGPT-6.1 Sol

- #1 tieSonnet 5.5

- #1 tieGemini 4 Argon

- #1 tieOpus 5.5

Ordering by hand decides Human rank and Human rate on the leaderboard; it never affects Overall or Strict.
Every model's attempts
Run hard-compact-2026-10-162026-10-16commit 6fa9f854spend $116.04 + $54.69 AI judging, 1 unpricedOther runs: 2026-09-23T06-56-16-hard-baseline-2026-09-23, 2026-09-10T19-44-23-baseline-2026-09, 2026-09-04T20-02-10-stage2-hard-cases, 2026-09-04T19-48-31-screen-14-fixed