FUNC-001 · Functional Intent · FEA-Gated · difficulty 5/5

Cantilever bracket — 250 N tip load, 6061-T6, SF≥4

sha256:33a91efbac0c1110…

§1Prompt verbatim

Design a cantilever bracket that bolts to a wall via two M6 holes 50 mm apart and supports a 250 N transverse tip load 80 mm from the wall, in 6061-T6 aluminium, with a static safety factor ≥ 4 against yield (σ_y = 276 MPa). Mass should be ≤ 60 g. Output STEP.

§2Ground-truth spec

shells1

watertighttrue

manifoldtrue

acceptance ε±0.1 mm

featuresM6_clearance_x2, load_pad

§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)

n=4 senior engineers

0.65211✗

OpenAI o4 (reasoning) → CadQuery

OpenAI + CadQuery 2.4

DeepSeek R1 (reasoning) → CadQuery

DeepSeek + CadQuery 2.4

0.43710✗

Claude Sonnet 4.6 → CadQuery

Anthropic + CadQuery 2.4

0.40412✗

GPT-5 → CadQuery

OpenAI + CadQuery 2.4

0.40216✗

Gemini 2.5 Flash → CadQuery

Google + CadQuery 2.4

0.34718✗

Claude Opus 4.7 → CadQuery

Anthropic + CadQuery 2.4

0.33917✗

GPT-5 Mini → OpenSCAD

OpenAI + OpenSCAD 2024.06

Qwen3 Coder → CadQuery

Alibaba + CadQuery 2.4

0.18827✗

CAD-Coder R1

CAD-Coder Labs (research)

0.18728✗

Llama 3.3 70B → OpenSCAD

Meta + OpenSCAD 2024.06

0.07563✗

Claude Haiku 4.5 → CadQuery

Anthropic + CadQuery 2.4

0.05781✗

no manifold solid produced

Gemini 2.5 Pro → OpenSCAD

Google + OpenSCAD 2024.06

—18✗

no manifold solid produced

Claude Opus 4.7 → OpenSCAD

Anthropic + OpenSCAD 2024.06

—18✗

DeepCAD

Wu et al. 2021 (research)

no manifold solid produced

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	Min-Wall Compliance	FEA-Yield Pass	p50	latency	cost
Human Baseline (Mech-E)	✓	0.948	0.912	0.828	0.729	—	700.5s	$5.421
OpenAI o4 (reasoning) → CadQuery	✓	0.940	0.761	0.626	0.709	—	98.6s	$1.007
Zoo Text-to-CAD	✓	0.918	0.702	0.684	0.486	—	4.5s	$0.172
DeepSeek R1 (reasoning) → CadQuery	✓	0.919	0.689	0.554	0.494	—	112.1s	$0.040
Claude Sonnet 4.6 → CadQuery	×	0.912	0.681	0.614	0.513	—	17.4s	$0.083
GPT-5 → CadQuery	×	0.910	0.685	0.639	0.523	—	53.2s	$0.244
Gemini 2.5 Flash → CadQuery	×	0.899	0.617	0.538	0.361	—	12.6s	$0.023
Claude Opus 4.7 → CadQuery	×	0.903	0.723	0.666	0.569	—	46.6s	$0.366
GPT-5 Mini → OpenSCAD	×	0.879	0.397	0.471	0.245	—	13.8s	$0.010
Adam (CADcrush)	×	0.879	0.729	0.596	0.385	—	10.2s	$0.270
Qwen3 Coder → CadQuery	×	0.880	0.570	0.521	0.366	—	18.3s	$0.031
CAD-Coder R1	×	0.878	0.677	0.542	0.269	—	7.0s	$0.005
Llama 3.3 70B → OpenSCAD	×	0.862	0.427	0.423	0.243	—	18.6s	$0.022
Claude Haiku 4.5 → CadQuery	×	0.859	0.485	0.465	0.282	—	6.0s	$0.017
Gemini 2.5 Pro → OpenSCAD kernel error: BRepCheck_NotClosed	×	0.000	—	—	—	—	29.6s	$0.084
Claude Opus 4.7 → OpenSCAD kernel error: BRepCheck_NotClosed	×	0.000	—	—	—	—	34.8s	$0.353
DeepCAD	×	0.850	0.486	0.381	0.188	—	6.0s	$0.021
Trellis 3D	×	0.850	0.212	0.216	0.086	—	11.4s	$0.056
Spline AI kernel error: BRepCheck_NotClosed	×	0.000	—	—	—	—	9.1s	$0.046
Hunyuan3D-2	×	0.850	0.208	0.221	0.093	—	45.1s	$0.064