step.parts: Instructions file for Codex

AGENTS.md

step.parts AGENTS.md is an instructions file for Codex, OpenCode from earthtojake/step.parts. It costs 2,574 tokens per session, scanned A, original, MIT.

A set of project instructions for a Next.js catalogue of open-source CAD parts, which are reusable 3D design components. STEP files and catalogue metadata are the source material; GLB models, PNG previews, and the SQLite database are generated outputs.

In plain words
What is it for?
Use it when adding parts, editing catalogue metadata, generating or syncing 3D previews, validating the catalogue, or running the app's type, lint, and build checks.
Why use it?
It clarifies which files are authoritative and which can be regenerated. This prevents unnecessary database or preview rebuilds and helps agents choose the correct command for metadata, assets, validation, or full checks.

Instructions file for CodexOpenCode

Written for Codex and OpenCode: the file is AGENTS.md.

This is earthtojake/step.parts's own configuration. It tells Codex and OpenCode how to work on step.parts itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything step.parts configures →

Reuse

Borrowing it

Nothing to install: this file belongs to earthtojake/step.parts. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file
curl -O https://raw.githubusercontent.com/earthtojake/step.parts/main/AGENTS.md
Clone the repo
git clone --depth 1 https://github.com/earthtojake/step.parts

Made for: Codex, OpenCode.

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 AGENTS.md

README.md
[![agentmods](https://agentmods.dev/badge/instructions/earthtojake/step.parts/agents-md.svg)](https://agentmods.dev/instructions/earthtojake/step.parts/agents-md)
Your own site
<a href="https://agentmods.dev/instructions/earthtojake/step.parts/agents-md"><img src="https://agentmods.dev/badge/instructions/earthtojake/step.parts/agents-md.svg" alt="Measured on agentmods" height="20"></a>
Per session 2,574 This file is loaded in full into every session.
When invoked 2,574 The same file — it is already loaded in full.
Security scan A 0 findings. Scan, not verified.
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 $0.02574 $0.02574
Opus 5 $0.01287 $0.01287
Sonnet 5 $0.00515 $0.00515
Haiku 4.5 $0.00257 $0.00257

Measured 6d ago against content hash cb28ab4966f9, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

step.parts AGENTS.md 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 6d 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.

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.

AGENTS.md · 173 lines

How it starts

The opening of the file, as written. The whole thing — 173 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Agent Guide

This repo is a Next.js catalog for open-source CAD parts. The source of truth is STEP files plus human-authored catalog metadata; GLB previews, PNG thumbnails, and the SQLite catalog are generated artifacts. Generated previews are published to Vercel Blob rather than committed.

Quick Commands

  • Dev server: npm run dev
  • Catalog SQLite metadata only: node scripts/generate-catalog.mjs
  • Catalog build: npm run catalog:build
  • Preview asset sync: npm run catalog:sync-assets
  • Non-mutating catalog validation: npm run catalog:check
  • Lint: npm run lint
  • TypeScript check: npx tsc --noEmit
  • Full app check: npm run check

npm run catalog:build rebuilds local GLB/PNG preview artifacts only; it does not update catalog/parts.sqlite. Preview Blob paths are derived from each part's STEP SHA-256, so SQLite is reproducible from source catalog metadata plus STEP files. Tune paired export lanes with STEP_PARTS_EXPORT_CONCURRENCY; it defaults to 2. Production npm run catalog:sync-assets uploads only missing deterministic Blob assets and generates local GLB/PNG files only for those missing parts.

For metadata-only changes to catalog/parts.json, do not run npm run catalog:build. Run node scripts/generate-catalog.mjs instead to refresh catalog/parts.sqlite without rebuilding GLB/PNG artifacts. Only run catalog:build when STEP files or preview assets need to be added, refreshed, or repaired.

The thumbnail exporter starts a local render server on 127.0.0.1; sandboxed runs may need approval/escalation.

Repo Shape

  • catalog/parts.json: human-authored part records only.
  • catalog/parts.sqlite: generated catalog metadata used by the app.
  • catalog/taxonomy.json: narrow guardrails for rigid, repeatable families only.
  • catalog/step/{id}.step: canonical STEP assets.
  • public/glb/{id}.glb: local generated interactive previews, ignored by Git and synced to Vercel Blob.
  • public/png/{id}.png: local generated 512x512 thumbnails, ignored by Git and synced to Vercel Blob.
  • scripts/add-part.mjs: single-part helper for local STEP files.
  • scripts/generate-catalog.mjs: regenerates catalog SQLite metadata only.
  • scripts/export-assets.mjs: converts STEP to GLB and renders PNGs.
  • scripts/check-catalog.mjs: validates source schema, taxonomy guardrails, STEP sanity, generated SQLite rows, and optionally published Blob assets.
  • src/components/part-directory.tsx: searchable catalog UI and card previews.
  • src/components/part-viewer.tsx: detail-page 3D viewer with PNG fallback.
  • src/lib/part-query.ts: server-side search/filter/sort behavior.
  • src/app/v1/*: catalog API routes.

Read the full file on GitHub · 173 lines

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. 6d ago First seen · 173 lines · 2,574 tokens per session scan A cb28ab4966f9

Subscribe to this mod's changes

step.parts AGENTS.md is an instructions file published in the GitHub repository earthtojake/step.parts (345 stars, last pushed 2mo ago), licensed MIT. It adds 2,574 tokens to every session, about $0.0129 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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