ASM-013 · Assembly & Mating · difficulty 4/5

Bayonet quarter-turn mount

sha256:16fb2e0d3c9011aa…

§1Prompt verbatim

Quarter-turn bayonet: outer ring Ø 30 mm with three lugs 4 × 3 mm at 0/120/240°, inner sleeve Ø 30.2 mm with matching slots. After 90° clockwise rotation the lugs must seat with axial clearance 0.10 ± 0.04 mm. Output assembly STEP showing the engaged state.

§2Ground-truth spec

shells2

watertighttrue

manifoldtrue

acceptance ε±0.02 mm

featuresbayonet_lug_x3

clearance[0.06, 0.14] mm

§3Reference render

canonical reference · drag to orbit, scroll to zoom

Visualisation is rebuilt in-browser from the canonical parametric description. Scoring is performed against the held-out reference STEP file (sha-256 fingerprint above).

§4Per-agent renders

reference + 10 agent outputs · scored against the held-out STEP

vol IoU · BREP · manifold

canonical reference

REFERENCE

canonical · ground truth

1.000100✓

Human Baseline (Mech-E)

OpenAI o4 (reasoning) → CadQuery

OpenAI + CadQuery 2.4

Claude Sonnet 4.6 → CadQuery

Anthropic + CadQuery 2.4

0.53212✗

GPT-5 → CadQuery

OpenAI + CadQuery 2.4

0.50510✗

DeepSeek R1 (reasoning) → CadQuery

DeepSeek + CadQuery 2.4

0.49612✗

DeepCAD

Wu et al. 2021 (research)

0.43814✗

CAD-Coder R1

CAD-Coder Labs (research)

0.39615✗

Gemini 2.5 Flash → CadQuery

Google + CadQuery 2.4

0.39213✗

Gemini 2.5 Pro → OpenSCAD

Google + OpenSCAD 2024.06

0.3710✗

GPT-5 Mini → OpenSCAD

OpenAI + OpenSCAD 2024.06

0.35115✗

Claude Opus 4.7 → OpenSCAD

Anthropic + OpenSCAD 2024.06

0.3100✗

Qwen3 Coder → CadQuery

Alibaba + CadQuery 2.4

0.26919✗

Claude Haiku 4.5 → CadQuery

Anthropic + CadQuery 2.4

0.24522✗

Llama 3.3 70B → OpenSCAD

Meta + OpenSCAD 2024.06

0.21822✗

no manifold solid produced

Claude Opus 4.7 → CadQuery

Anthropic + CadQuery 2.4

Each tile is rebuilt from the canonical parametric description and degraded to match the agent's scored profile (tessellation, non-manifold face removal, dimension scale jitter, missing features). Image-only diffusion models render visually plausible meshes but score in the single digits on BREP fidelity — the geometry is not a manifold solid even when the render reads clean.

§5Per-agent metrics

ranked by Vol IoU · same data as the leaderboard, restricted to this task

Agent	Watert.	Manif.	FeatRec	Mating Clearance	Fit-Class Compliance	P@1	p50	latency	cost
Human Baseline (Mech-E)	✓	0.971	0.872	0.789	0.828	1.000	—	851.0s	$5.666
Zoo Text-to-CAD	✓	0.964	0.728	0.671	0.551	1.000	—	6.3s	$0.212
OpenAI o4 (reasoning) → CadQuery	✓	0.946	0.746	0.608	0.484	0.000	—	90.9s	$1.274
Adam (CADcrush)	✓	0.929	0.681	0.606	0.479	0.000	—	7.2s	$0.278
Claude Sonnet 4.6 → CadQuery	✓	0.937	0.641	0.573	0.369	0.000	—	23.2s	$0.083
GPT-5 → CadQuery	✓	0.932	0.730	0.596	0.400	0.000	—	34.4s	$0.179
DeepSeek R1 (reasoning) → CadQuery	✓	0.923	0.643	0.537	0.314	0.000	—	74.0s	$0.042
DeepCAD	✓	0.916	0.452	0.417	0.162	0.000	—	4.3s	$0.018
CAD-Coder R1	×	0.913	0.689	0.534	0.245	0.000	—	4.8s	$0.004
Gemini 2.5 Flash → CadQuery	×	0.909	0.553	0.449	0.241	0.000	—	15.1s	$0.021
Gemini 2.5 Pro → OpenSCAD	×	0.910	0.523	0.472	0.218	0.000	—	21.4s	$0.094
GPT-5 Mini → OpenSCAD	×	0.903	0.398	0.381	0.108	0.000	—	15.1s	$0.010
Claude Opus 4.7 → OpenSCAD	×	0.894	0.556	0.490	0.237	0.000	—	37.5s	$0.315
Qwen3 Coder → CadQuery	×	0.889	0.618	0.516	0.213	0.000	—	23.3s	$0.033
Claude Haiku 4.5 → CadQuery	×	0.885	0.529	0.411	0.155	0.000	—	7.8s	$0.023
Llama 3.3 70B → OpenSCAD	×	0.883	0.419	0.358	0.114	0.000	—	20.8s	$0.024
Claude Opus 4.7 → CadQuery kernel error: BRepCheck_NotClosed	×	0.000	—	—	—	0.000	—	49.3s	$0.388
Trellis 3D	×	0.850	0.205	0.082	0.006	0.000	—	14.1s	$0.057
Spline AI	×	0.850	0.093	0.049	0.001	0.000	—	9.1s	$0.041
Hunyuan3D-2	×	0.850	0.201	0.092	0.006	0.000	—	32.7s	$0.076