simplecadapi

simplecadapi is a skill for Claude Code, Codex from NiJingzhe/SimpleCADAPI. It costs 65 tokens per session (2,046 once invoked), scanned A, original, Apache-2.0.

A Python toolkit for creating, inspecting, rebuilding, and exporting parametric CAD models. CAD is computer-aided design: software used to define precise parts and assemblies for products.

In plain words
What is it for?
Use it to make constrained sketches, parts, assemblies, gears, and bearings; inspect or reconstruct CAD files; and export durable product packages or replayable model data.
Why use it?
It gives coding agents a defined way to work with SimpleCAD geometry instead of guessing at the SDK's API. It also supports repeatable model files and checks for formats such as STEP and BREP.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one.

Good fit Use it to make constrained sketches, parts, assemblies, gears, and bearings; inspect or reconstruct CAD files; and export durable product packages or replayable model data.

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Install with agentmods
npx agentmods add skills/nijingzhe/simplecadapi/skill
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 NiJingzhe/SimpleCADAPI --skill skill
Clone the repo
git clone --depth 1 https://github.com/NiJingzhe/SimpleCADAPI

Made for: Claude Code, Codex.

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 simplecadapi

README.md
[![agentmods](https://agentmods.dev/badge/skills/nijingzhe/simplecadapi/skill/github.svg)](https://agentmods.dev/skills/nijingzhe/simplecadapi/skill)
Your own site
<a href="https://agentmods.dev/skills/nijingzhe/simplecadapi/skill"><img src="https://agentmods.dev/badge/skills/nijingzhe/simplecadapi/skill/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 simplecadapi

Your own site · 80×15
<a href="https://agentmods.dev/skills/nijingzhe/simplecadapi/skill"><img src="https://agentmods.dev/badge/skills/nijingzhe/simplecadapi/skill.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 65 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,046 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.
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 $0.00065 $0.02046
Opus 5 $0.00032 $0.01023
Sonnet 5 $0.00013 $0.00409
Haiku 4.5 $0.00006 $0.00205

Measured yesterday against content hash 7737e6c3531c, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-08, from the pricing page.

Security

Grade A, and why

simplecadapi 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 yesterday.

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.

docs/skill/SKILL.md · 187 lines

How it starts

The opening of the file, as written. The whole thing — 187 lines — stays where its author put it; the contents beside it link to each section on GitHub.

SimpleCAD SDK Skill

This file is the router: it owns load order, route selection, and execution discipline only. Each selected workflow owns its procedure. Classify the request, load exactly one workflow, follow its domain and discipline references, and read exact API pages for the APIs its steps use.

Mandatory load order

Paths are relative to this file's directory.

  1. Read this file.
  2. Select exactly one workflow from Task routing. If two rows plausibly match, ask one discriminator question that names the candidate outcomes; never pick silently between routes with different deliverables.
  3. Read the selected workflow in full. From selection on, it owns the procedure; do not load another workflow's procedure.
  4. Load each required domain/discipline file the workflow names before the step that uses it; optional ones only when their trigger fires.
  5. Before the first call of any API, read its exact page (references/docs/api/<name>.md, references/docs/stdlib/<name>.md, references/docs/core/<type>.md). A method absent from its page does not exist, however plausible it looks.
  • You MUST NOT read the full API or stdlib index up front; the workflow names every page its steps need.
  • Routing questions are decided here; after selection the workflow owns execution. You MUST always follow the global rules and execution discipline below.
  • Questions about an existing STEP file that change nothing enter no workflow; you MUST use references/domains/step-inspection.md for them directly.

Task routing

Read exactly one workflow first, per the user's goal:

User goal Workflow
Model one physical part references/workflows/single-part-modeling.md
Multi-part product or mechanism (custom parts, stdlib gears/bearings, connectors, constraints, package) references/workflows/assembly-product-build.md
Rebuild an editable model from a STEP file references/workflows/step-reconstruction.md
Export/translate a validated package references/workflows/export-and-translation.md
Produce a GB engineering drawing (DXF) from validated geometry references/workflows/engineering-drawing.md

Read the full file on GitHub · 187 lines

Files

What ships with it

60 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. yesterday First seen · 187 lines · 65 tokens per session scan A 7737e6c3531c

Subscribe to this mod's changes

simplecadapi is a skill published in the GitHub repository NiJingzhe/SimpleCADAPI (112 stars, last pushed yesterday), licensed Apache-2.0. It adds 65 tokens to every session and 2,046 once invoked, about $0.0003 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 2026-09-07.

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