build123d-cad-drafting-skill

Automate CAD drafting workflows with build123d builder modes and semantic selectors.

2|Updated Jan 31, 2026

Search Tags:#constraints #drafting #assembly #placement #build123d #cad #mjcf

Ready to run

npx skills add https://github.com/MRiabov/Problemologist-AI --skill build123d-cad-drafting-skill

💬 Prompt for ChatGPT / Claude Chat▼

Please help me install this Agent Skill.
Skill: build123d-cad-drafting-skill
Source: https://github.com/MRiabov/Problemologist-AI/tree/main/.agents/skills/build123d-cad-drafting-skill
Command: npx skills add https://github.com/MRiabov/Problemologist-AI --skill build123d-cad-drafting-skill

SYSTEM DOCUMENTATION & REQUIREMENTS

What problem does it solve?

build123d allows engineers to draft CAD models programmatically with builder modes, semantic selectors, and MJCF-compatible boolean strategies, providing a repeatable, rule-based workflow for complex mechanical designs.

Core Features & Use Cases

Builder-mode CAD construction using BuildPart, BuildSketch, and boolean operations with strict dimensioning and metadata patterns.
Semantic selectors and placement rules to reduce manual coordinate tuning and avoid hard-coded indices.
MJCF-compatible assembly and motor/machine-translation guidance enabling safer, manufacturable prototypes and simulations.
Use cases include rapid parametric prototyping, constraint-driven assembly planning, and design-for-manufacturability verification.

Quick Start

Plan and execute a parametric CAD task using build123d by defining inputs, selecting primitives, applying constraints, and exporting a final assembly.

Frequently Asked Questions about build123d-cad-drafting-skill

High-intent search queries and answers about installing and using this skill.

FAQPage Schema

How do I automate parametric CAD drafting with build123d?▼

Automate parametric CAD drafting using build123d by defining inputs, selecting primitives, applying constraints, and exporting a final assembly. It uses builder modes and semantic selectors to reduce manual coordinate tuning.

What is the best way to plan constraint-driven assemblies for mechanical prototypes?▼

Constraint-driven assembly planning is best handled by using build123d's builder modes and semantic selectors. This approach applies strict dimensioning rules to generate manufacturable prototypes and verify design-for-manufacturability.

Does build123d support MJCF-compatible assembly workflows for simulation?▼

Yes, build123d supports MJCF-compatible assembly workflows. It provides boolean strategies and machine-translation guidance to create safer, manufacturable prototypes suitable for machine simulations.

How do semantic selectors improve CAD part placement?▼

Semantic selectors improve CAD part placement by targeting geometry conceptually rather than by hard-coded indices. This reduces manual coordinate tuning and ensures accurate, constraint-driven placement in assemblies.

Can I use build123d for design-for-manufacturability checks?▼

Yes, you can use build123d for design-for-manufacturability checks. It enables rule-based parametric part creation and strict dimensioning patterns to verify manufacturable prototypes within a controlled CAD environment.