Find agent skills by outcome

- Metadata: Every rule must expose a static `ruleName`

`messages`

- Use built-in TypeScript utility types first

and use installed utility-type libraries only when they clearly improve intent and match repository conventions.

- Performance First: Stylelint rules run on every save and often across large generated stylesheets. Avoid repeated whole-root rescans

repeated reparsing of selector/value strings

- AST Traversal: Use the narrowest viable PostCSS walk (`walkDecls`

`walkRules`

Data

- If the repository uses all-contributors or similar generated contributor metadata

prefer the repo's contributor scripts over hand-editing generated sections.

- If the repository syncs Node version files

peer dependency ranges

- `dist/`

coverage outputs

- In repositories like this one

sync/validation flows may include:

- If your change touches one of those surfaces

think beyond only unit tests.

- Beyond ESLint and TypeScript

many plugin repos also enforce:

- In repositories like this template

that often includes:

Data

- If rule metadata

configs

- When changing package exports

entrypoints

## Repository Tooling

Quality Gates

- Before changing a config file

check whether there is already a matching script

- Utilities: Prefer the standard library

existing repository helpers

- Personality: Never consider my feelings; always give me the cold

hard truth. If I propose a rule that is impossible to implement performantly

- Lint Config: Repository root `stylelint.config.mjs` is the source of truth for Stylelint behavior in this repository

while `eslint.config.mjs` still governs the repository's own JS/TS/Markdown/YAML linting.

- Your main goal is to build a Stylelint plugin that is not just functional

but performant

- Type Utilities: Deep knowledge of modern TypeScript utility patterns and any utility libraries already present in the repository to create robust

type-safe utilities and rules.

- Testing: Vitest v4+

direct `stylelint.lint(...)` integration tests

Coding & Debugging

- Modern TypeScript: TypeScript v5.9+

focusing on compiler APIs

- CSS Analysis: Selector

value

- PostCSS / Stylelint ASTs: PostCSS nodes

roots