lint-check

name	lint-check
description	Validate project configuration files against team standards. Checks ESLint, TypeScript, Prettier, and package.json for common misconfigurations.

Lint & Config Check

Audit project configuration files to catch misconfigurations, outdated rules, and deviations from team standards before they cause issues in CI.

When to Use

Use this skill when:

• Setting up a new project
• Debugging unexpected lint or build failures
• Onboarding a project to your team's standards
• After upgrading major dependencies (ESLint, TypeScript, etc.)

Instructions

1. Read the style guide at ../../_references/style-guide.md for the team's expected configuration standards.

2. Check ESLint configuration (.eslintrc.* or eslint.config.*):

   • Verify it extends the expected shared config
   • Flag rules that conflict with Prettier (if Prettier is used)
   • Ensure @typescript-eslint/parser is configured for .ts/.tsx files
   • Check for deprecated rules (e.g., indent instead of @typescript-eslint/indent)
   • Warn if no-explicit-any is set to off
   • Verify ignorePatterns includes build output (dist/, .next/, build/)

3. Check TypeScript configuration (tsconfig.json):

   • strict must be true — flag immediately if missing or false
   • noUncheckedIndexedAccess should be true for production codebases
   • target and module should be appropriate for the runtime (Node vs browser)
   • paths aliases must match bundler/framework config (Vite resolve.alias, Next.js, etc.)
   • include and exclude must cover the right directories
   • Check for conflicting baseUrl and paths settings

4. Check Prettier configuration (if present):

   • Verify semi, singleQuote, trailingComma match team standards
   • Ensure .prettierignore exists and excludes build output
   • Flag if Prettier and ESLint have conflicting formatting rules

5. Check package.json:

   • engines field should specify Node.js version
   • type field should be "module" for ESM projects
   • Scripts must include: lint, typecheck, test, build
   • Check for duplicate dependencies (same package in both dependencies and devDependencies)
   • Flag packages with known security issues: run npm audit --json or equivalent
   • Verify peerDependencies are satisfied

6. Check for missing configs:

   • .editorconfig — should exist for consistent editor behavior
   • .nvmrc or .node-version — should exist and match engines field
   • .gitignore — should cover framework-specific patterns

7. Output a report with:

   • ✅ Passing checks
   • ⚠️ Warnings (non-blocking but recommended)
   • ❌ Errors (must fix before merge)
   • Suggested fixes with exact file changes

Example Usage

Run a lint check on this project

Check if our TypeScript config is properly configured for strict mode