step-parts

step-parts is a skill for Claude Code, Codex from earthtojake/text-to-cad. It costs 119 tokens per session (1,334 once invoked), scanned A, original, MIT.

A tool for finding and downloading ready-made CAD parts from the step.parts catalogue. CAD parts are digital 3D models of physical components such as motors, connectors, screws, bearings, and electronics boards.

In plain words
What is it for?
Use it when creating a CAD assembly that includes named off-the-shelf hardware and you need its actual 3D model.
Why use it?
It helps avoid drawing simplified replacements when a real, purchasable component is already available. It also accounts for alternate model names and vendor spellings when searching.

Skill for Claude CodeCodex

Written for Claude Code and Codex: shipped in a Claude Code plugin, but also agents/openai.yaml present. Also seen: mentions Codex; $skill-name invocation.

Part of the cad plugin — 12 skills shipped together

Good fit Use it when creating a CAD assembly that includes named off-the-shelf hardware and you need its actual 3D model.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/earthtojake/text-to-cad/step-parts
About the project

text-to-cad is a collection of agent workflows for creating, examining, finding, preparing, and transferring CAD, engineering, manufacturing, and robot-description files. It is for agents working with mechanical design, fabrication, simulation, and robotics projects. Catalogue skills, instructions, and a plugin implement these workflows.

earthtojake/text-to-cad · 15,369 stars · on GitHub · texttocad.dev

Install

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.

Any agent
npx skills add earthtojake/text-to-cad --skill step-parts
Clone the repo
git clone --depth 1 https://github.com/earthtojake/text-to-cad

Made for: Claude Code, Codex.

Or install cad, the plugin that ships this one along with the rest of its 12 skills.

Wrote 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.

agentmods badge for step-parts

README.md
[![agentmods](https://agentmods.dev/badge/skills/earthtojake/text-to-cad/step-parts/github.svg)](https://agentmods.dev/skills/earthtojake/text-to-cad/step-parts)
Your own site
<a href="https://agentmods.dev/skills/earthtojake/text-to-cad/step-parts"><img src="https://agentmods.dev/badge/skills/earthtojake/text-to-cad/step-parts/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.

agentmods 80×15 button for step-parts

Your own site · 80×15
<a href="https://agentmods.dev/skills/earthtojake/text-to-cad/step-parts"><img src="https://agentmods.dev/badge/skills/earthtojake/text-to-cad/step-parts.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 119 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,334 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe. Third-party audits
  • Socket pass 14 May 2026
  • Snyk warn 14 May 2026
  • NVIDIA SkillSpector pass 7 Sept 2026
How audits are shown
Origin original No closer match found in the catalogue.
Token cost

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.

ModelPer sessionOnce invoked
Fable 5.1 $0.00119 $0.01334
Opus 5 $0.00060 $0.00667
Sonnet 5 $0.00024 $0.00267
Haiku 4.5 $0.00012 $0.00133

Measured 13d ago against content hash 5f9bccf3beaf, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-12, from the pricing page.

Security

Grade A, and why

step-parts scanned grade A with 0 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 13d ago.

The scan reads SKILL.md. This mod also ships 1 executable file (scripts/download_step_part.py), listed below but not scanned — reading those needs a real analyzer, not pattern matching.

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.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

Origin

Copies of this mod

2 near-identical copies found in the catalogue:

skills/step-parts/SKILL.md · 71 lines

How it starts

The opening of the file, as written. The whole thing — 71 lines — stays where its author put it; the contents beside it link to each section on GitHub.

CAD Parts

Provenance: maintained in earthtojake/text-to-cad. Use the installed local skill files as the runtime source of truth; the repository link is only for provenance and release review.

Overview

Use the hosted step.parts machine endpoints instead of scraping HTML or relying on local repository files. Treat https://api.step.parts as the canonical API origin and https://www.step.parts as the site/static-asset origin unless the user provides a different hosted mirror. Network/DNS failures are inconclusive: if api.step.parts cannot be reached from the sandbox, retry once with network permission before reporting a miss or using placeholder geometry. Do not describe a part as unavailable unless the API was reachable and returned no relevant candidates.

When a CAD assembly includes named off-the-shelf actuators, servos, motors, electronics boards, connectors, or other purchasable components, search step.parts before creating simplified placeholder geometry. For named servos, motors, and actuators, search both exact model strings and common aliases/vendor spellings before giving up. For example, STS3215 may also appear as ST3215, 3215, Waveshare Feetech ST3215, or under family=feetech. If the API was reachable and no exact or near-exact match is available, record the search miss and then use a documented envelope or simplified stand-in.

Quick Workflow

  1. Interpret the requested part into search terms and optional facets:
    • q for fuzzy tokens, standards, aliases, dimensions, source/product URLs, and attribute names/values.
    • category, family, standard, or tag when the user gives an exact facet.
  2. Search /v1/parts and inspect items, total, and facets. For actuator model numbers, retry likely aliases, dropped letters, vendor names, and relevant family facets before treating an empty result as a miss.
  3. If results are ambiguous, present the best few options with id, name, standard, and key attributes before choosing. If one result clearly matches, return the selected record details without downloading unless the user asked for a local STEP file.
  4. When an exact or near-exact off-the-shelf actuator model is found, prefer downloading and using its STEP file unless there is a clear assembly-time reason to use a simplified envelope. Record that choice explicitly.
  5. When the user asks to download or save a STEP file, download its stepUrl, then verify the file with the record's sha256 when present.
  6. Return the local path when downloaded, plus the selected part id and page/API URLs so the user can trace provenance.

Read the full file on GitHub · 71 lines

Files

What ships with it

4 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.

Changes

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.

  1. 13d ago First seen · 71 lines · 119 tokens per session scan A 5f9bccf3beaf

Subscribe to this mod's changes

step-parts is a skill published in the GitHub repository earthtojake/text-to-cad (15,369 stars, last pushed yesterday), licensed MIT. It adds 119 tokens to every session and 1,334 once invoked, about $0.0006 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

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