project-structure

A set of project-organization rules for folders, filenames, types, re-exports, and import paths. It groups related code by feature instead of only by file type.

In plain words
What is it for?
Use it when adding or reorganizing application features, components, hooks, utilities, tests, types, and imports.
Why use it?
It makes related code easier to find and avoids oversized shared type files, unnecessary re-export files, and unclear imports.

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/tonyghiani/ai-essentials/project-structure
Clone the repo
git clone --depth 1 https://github.com/tonyghiani/ai-essentials
Per session 0 Nothing until a file matches its globs; then the whole rule loads.
When invoked 420 The whole file, excluding the scripts and references it only reads on demand.
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 $0.00000 $0.00420
Opus 5 $0.00000 $0.00210
Sonnet 5 $0.00000 $0.00084
Haiku 4.5 $0.00000 $0.00042

Measured 2d ago against content hash f76993547f01, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

project-structure 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/project-structure.mdc · 48 lines

What it actually says

Project conventions win. Read the surrounding tree first; these apply when adding a new area.

Folders

❌ components/ hooks/ utils/ types/ // grouped by kind ✅ pages/significant_events/components/streams_view/ streams_view.tsx utils.ts utils.test.ts Feature folders. Top-level components/, hooks/, util/ only for genuinely cross-feature code.

❌ streams_view/index.tsx // when the folder also holds tests, hooks, utils ✅ streams_view/streams_view.tsx index.tsx only when the folder holds a lone component and nothing else.

Files and folders are snake_case, hooks included: use_device.ts. One hook per file, named for it.

Barrels

❌ components/index.ts re-exporting every sibling ✅ import { StreamsView } from './streams_view/streams_view'; No barrels in app code; import from the defining file. A barrel is a published package's public entry point, nothing else. Delete dead re-exports when you find them.

Types

❌ src/types.ts holding every domain model ✅ the type lives with the module that owns it; shared types move to the closest common ancestor

Imports

✅ import { StreamsView } from './streams_view/streams_view'; // within a feature ✅ import { formatDate } from '@/utils/date'; // across features or packages

❌ import { type IFoo, bar } from './foo'; ✅ import type { IFoo } from './foo'; import { bar } from './foo'; Inline type only when values and types genuinely come from one module.

Circular dependencies are banned. Break the cycle by extracting the shared piece. Import ordering is enforced by simple-import-sort; do not hand-sort. See eslint-recommendations.md for the group configuration.

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 · 48 lines · 0 tokens per session scan A f76993547f01

Subscribe to this mod's changes

project-structure is a cursor rule published in the GitHub repository tonyghiani/ai-essentials (6 stars, last pushed 24d ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 420 tokens. 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 2026-08-31.