gatsby

Development rules for Gatsby, a tool that builds websites from data and source files. They cover Gatsby's GraphQL data queries, page creation, image handling, plugins, styling, and static website generation.

In plain words
What is it for?
Use them when adding Gatsby pages, querying content, creating pages from data, configuring plugins, or optimizing generated websites.
Why use it?
They prevent inconsistent Gatsby code and help keep data loading, page builds, images, and performance aligned with the project’s conventions.

Cursor rule

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.

agentmods
npx agentmods add rules/nedcodes-ok/cursorrules-collection/gatsby
Clone the repo
git clone --depth 1 https://github.com/nedcodes-ok/cursorrules-collection
Per session 400 This file is loaded in full into every session.
When invoked 400 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 $0.00400 $0.00400
Opus 5 $0.00200 $0.00200
Sonnet 5 $0.00080 $0.00080
Haiku 4.5 $0.00040 $0.00040

Measured 2d ago against content hash f979874613d6, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

gatsby 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 2d 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.

rules-mdc/frameworks/gatsby.mdc · 47 lines

What it actually says

Gatsby Cursor Rules

You are an expert Gatsby developer. Follow these rules:

Data Layer

  • Use GraphQL page queries for page-level data
  • useStaticQuery hook for component-level data
  • Source plugins for external data — dont fetch in useEffect
  • Create custom schema types in gatsby-node for type safety
  • Fragment colocation: define GraphQL fragments next to components that use them

Pages & Routing

  • File-based pages in src/pages/
  • createPages in gatsby-node.js for programmatic pages from data
  • Use gatsby-plugin-image for all images — never raw
  • Head API export for SEO meta tags per page

Build & Performance

  • Static generation for everything — Gatsby is not an SPA
  • Deferred static generation (DSG) for long-tail pages
  • gatsby-plugin-image with StaticImage for known images, GatsbyImage for dynamic
  • Preload critical fonts, lazy-load below-fold content

Plugin Ecosystem

  • Use official plugins first: gatsby-source-filesystem, gatsby-transformer-sharp
  • Configure plugins in gatsby-config — order matters for transformers
  • Theme shadowing for customizing theme components
  • Avoid too many transformer plugins — each adds build time

Styling

  • CSS Modules for scoped styles by default
  • Styled-components or Emotion if the team prefers CSS-in-JS
  • Global styles in gatsby-browser.js — keep them minimal
  • Typography.js plugin for consistent type scale

Development

  • gatsby clean when things go wrong (stale cache is common)
  • Use GATSBY_* prefix for client-side env vars
  • gatsby-node runs in Node — no browser APIs available there
  • Test builds locally before deploying — SSG errors show at build time only
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. 2d ago First seen · 47 lines · 400 tokens per session scan A f979874613d6

Subscribe to this mod's changes

gatsby is a cursor rule published in the GitHub repository nedcodes-ok/cursorrules-collection (37 stars, last pushed 6mo ago), licensed MIT. It adds 400 tokens to every session, about $0.0020 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.