Find agent skills by outcome

- When finishing a task or request

review everything from the lens of code quality

- Error Handling: When parsing weird syntax

fail gracefully. Do not crash the linter process.

- Break down PostCSS traversal logic into small

testable utility functions.

- Custom Syntax Awareness: When a rule depends on syntax that does not exist in plain CSS

scope it carefully and document the expected `customSyntax` or file context.

- Utility Usage: Before writing a helper function

check whether the standard library

3. Edge cases (nested rules

comments

- Fixers: Only mark a rule as `meta.fixable = true` when the fix is deterministic and safe across supported syntaxes. If a fix is risky

report only.

- 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`

- `dist/`

coverage outputs

- If the repository syncs Node version files

peer dependency ranges

- 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 one

sync/validation flows may include:

- In repositories like this template

that often includes:

- 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

- 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

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

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

Coding & Debugging

- Modern TypeScript: TypeScript v5.9+

focusing on compiler APIs