Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx skills add rawwerks/VibeCAD --skill build123dgit clone --depth 1 https://github.com/rawwerks/VibeCADWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/rawwerks/vibecad/build123d)<a href="https://agentmods.dev/skills/rawwerks/vibecad/build123d"><img src="https://agentmods.dev/badge/skills/rawwerks/vibecad/build123d/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/rawwerks/vibecad/build123d"><img src="https://agentmods.dev/badge/skills/rawwerks/vibecad/build123d.svg" alt="Reviewed on agentmods" width="80" height="20"></a>What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00138 | $0.01580 |
| Opus 5 | $0.00069 | $0.00790 |
| Sonnet 5 | $0.00028 | $0.00316 |
| Haiku 4.5 | $0.00014 | $0.00158 |
Grade C, and why
build123d scanned grade C with 2 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 10d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Downloads and executes remote codehighSupply chain
curl | sh runs whatever the server returns today, which is not necessarily what it returned when this was reviewed.
curl -LsSf https://astral.sh/uv/install.sh | sh Makes network callslowCapability
Not a fault in itself. Listed so you know the mod talks to something, and to what.
curl -LsSf https://astral.sh/uv/install.sh | sh How it starts
The opening of the file, as written. The whole thing — 192 lines — stays where its author put it; the contents beside it link to each section on GitHub.
build123d CAD Modeling
Zero-Setup with uv
No installation required. Run any build123d script with:
uvx --from build123d python script.py
This automatically downloads build123d and runs your script. First run takes ~30s, subsequent runs are instant.
Install uv (if not already installed):
curl -LsSf https://astral.sh/uv/install.sh | sh
Critical: Imports
All exports are in the main module:
from build123d import Sphere, Box, Cylinder, export_gltf, export_step, export_stl
NEVER use from build123d.exporters import ... - this module does not exist.
Quick Start Example
#!/usr/bin/env python3
from build123d import Sphere, Box, export_gltf, Pos
# Create shapes
sphere = Sphere(radius=20)
box = Pos(15, 0, 0) * Box(10, 10, 10)
# Boolean union
result = sphere + box
# Export to GLB (for web viewers, Three.js)
export_gltf(result, "./model.glb", binary=True)
print("Exported model.glb")
Run it:
uvx --from build123d python my_model.py
Geometry Inspection (Optional)
To inspect geometry properties, add this to your script:
def inspect(shape):
bbox = shape.bounding_box()
print(f"Size: {bbox.max.X - bbox.min.X:.1f} x {bbox.max.Y - bbox.min.Y:.1f} x {bbox.max.Z - bbox.min.Z:.1f}")
print(f"Volume: {shape.volume:.1f}")
print(f"Faces: {len(shape.faces())}, Edges: {len(shape.edges())}")
inspect(result)
A full inspection harness is available in scripts/harness.py for advanced use.
Quick Reference
Shapes
Box(length, width, height)
Sphere(radius=20)
Cylinder(radius=10, height=25)
Cone(bottom_radius=15, top_radius=5, height=20)
Torus(major_radius=20, minor_radius=5)
Boolean Operations
union = shape1 + shape2 # Fuse
difference = shape1 - shape2 # Cut
intersection = shape1 & shape2 # Common volume
Positioning
from build123d import Pos, Rot
moved = Pos(x, y, z) * shape # Translate
rotated = Rot(rx, ry, rz) * shape # Rotate (degrees)
What ships with it
39 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
- references/advanced-patterns.md 6.0 KB
- references/bd-warehouse-reference.md 6.4 KB
- references/examples/01_simple_shapes.py 781 B runs code
- references/examples/02_boolean_operations.py 1019 B runs code
- references/examples/03_export_formats.py 1002 B runs code
- references/examples/04_positioning.py 864 B runs code
- references/examples/05_sketch_extrude.py 859 B runs code
- references/examples/06_fillet_chamfer.py 656 B runs code
- references/examples/07_csg_classic.py 917 B runs code
- references/examples/08_hole_pattern.py 746 B runs code
- references/examples/09_bd_warehouse_threads.py 1.8 KB runs code
- references/examples/10_bd_warehouse_fasteners.py 1.8 KB runs code
- references/examples/11_bd_warehouse_gears.py 2.0 KB runs code
- references/examples/12_bd_warehouse_pipes.py 1.6 KB runs code
- references/examples/13_bd_warehouse_flanges.py 2.2 KB runs code
- references/examples/14_bd_warehouse_bearings.py 2.0 KB runs code
- references/examples/15_gggears_spur.py 1.4 KB runs code
- references/examples/16_gggears_helical.py 2.0 KB runs code
- references/examples/17_gggears_bevel.py 1.6 KB runs code
- references/examples/18_gggears_planetary.py 2.2 KB runs code
- references/examples/19_gggears_cycloid.py 1.5 KB runs code
- references/examples/20_gggears_rack.py 1.9 KB runs code
- references/examples/21_split_and_mirror.py 1.8 KB runs code
- references/examples/22_plane_offsets_positions.py 1.2 KB runs code
- references/examples/23_stadium_slotoverall.py 1.6 KB runs code
- references/examples/24_intersection_corners.py 1.0 KB runs code
- references/examples/25_face_local_coordinates.py 1.1 KB runs code
- references/examples/26_construction_sequence.py 1.4 KB runs code
- references/examples/27_profile_vs_primitives.py 1.8 KB runs code
- references/examples/dual_color_3mf.py 2.2 KB runs code
- references/examples/loft.py 1.5 KB runs code
- references/examples/packed_boxes.py 1.2 KB runs code
- references/examples/roller_coaster.py 1.5 KB runs code
- references/examples/tea_cup.py 3.8 KB runs code
- references/examples/toy_truck.py 6.1 KB runs code
- references/examples/vase.py 2.7 KB runs code
- references/gggears-reference.md 7.2 KB
- references/quick-reference.md 3.8 KB
- scripts/harness.py 5.7 KB runs code
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 10d ago First seen · 192 lines · 0 tokens per session scan C d1ca04b5c9a4
build123d is a skill published in the GitHub repository rawwerks/VibeCAD (117 stars, last pushed 8mo ago), licensed MIT. It adds 138 tokens to every session and 1,580 once invoked, about $0.0007 per session on Opus 5. A static security scan graded it C with 2 findings (downloads and executes remote code, makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
Other skills, from other repositories
systematic-debugging
Use when encountering any bug, test failure, or unexpected behavior, before proposing fixes.
local-ai-agents
Build local-first AI agents that run entirely on a developer workstation with Microsoft Foundry Local and Qwen function-calling models. Covers Small Language Models (SLMs), the OpenAI-compatible local endpoint, sandboxed local tools, local RAG with Chroma, local MCP servers, hybrid cloud/local routing, and the…
next-cache-components-adoption
Turn on Cache Components in a Next.js app and resolve the blocking routes it surfaces. Use when the user wants to enable, adopt, or migrate to Cache Components, flip the cacheComponents flag, work through a flood of blocking-prerender / instant validation errors, run the cache-components-instant-false codemod, or…
insight-error-page
Write or audit an insight-kind error page for the Next.js dev overlay. Use when creating a new errors/ .mdx page, auditing an existing one, or checking that a page matches the framework fix cards. Covers page structure, title alignment, FixCard cards with Copy prompt button, code snippets, terminology verification…
next-cache-components-optimizer
Drive a Next.js route to instant navigation by setting up an agentic loop, under Cache Components / PPR, on initial load (hard navigation) and client-side navigation (soft navigation). Encode the goal as a failing @next/playwright instant() e2e and work it to green, one verified route at a time; the shipped test then…
next-partial-prefetching-adoption
Turn on Partial Prefetching in a Next.js app and work through the insights it surfaces. Use when the user wants to enable or adopt Partial Prefetching, flip the partialPrefetching flag, opt routes in with export const prefetch = 'partial', audit Link prefetch={true} behavior, preserve existing prefetched UI with…