quality-fix

name	quality-fix
description	Use this skill when the user asks to fix linting errors, resolve pre-commit hook failures, fix TypeScript errors, fix Biome issues, or when the lefthook pre-commit check is blocking a commit. Trigger phrases: "fix lint errors", "lefthook fails", "pre-commit failed", "biome errors", "ts errors", "run check", "quality check", "npm run check", "validate project".

Quality Fix

Resolves issues caught by the project's quality gate.

Quality Gate Pipeline

npm run check runs these tools in parallel:

1. stylelint — CSS/SCSS linting
2. tsc --noEmit — TypeScript type checking
3. biome check --write — JS/TS linting + auto-format
4. knip --production — dead code and unused exports/deps
5. steiger ./src — FSD architectural boundary checks

This same pipeline runs on every git commit via Lefthook.

Step 1: Run the full check

npm run check

Read the output carefully — each tool reports separately.

Step 2: Fix by tool

Biome (TypeScript/JS linting + formatting)

Biome auto-fixes most issues:

npm run lint:fix          # Safe auto-fixes
npm run lint:fix:unsafe   # Also unsafe fixes (use with caution)

Common manual fixes:

• Unused import — delete the import line
• Unused variable — delete or prefix with _ if intentional
• any type — replace with a proper type or unknown
• Missing return type — add explicit return type annotation

TypeScript (tsc --noEmit)

npm run ts:check

Common fixes:

• Type mismatch — align types between caller and callee
• Missing property — add to interface or mark optional with ?
• Implicit any — add explicit type annotation

Stylelint (CSS/SCSS)

npm run lint:style:fix   # Auto-fix
npm run lint:style       # Check only

Knip (dead code / unused exports)

npm run knip

Knip reports:

• Unused exports — remove the export or add a consumer
• Unused files — delete the file or import it somewhere
• Unused dependencies — remove from package.json

Do not suppress Knip errors with ignores unless the export is intentionally part of a public API.

Steiger (FSD boundaries)

npm run lint:fsd

FSD violations to fix:

• Cross-layer import — entity importing from feature → move logic or use a different pattern
• Cross-slice import — one feature directly importing from another feature → extract to shared or use events

See the refactor-fsd skill for refactoring guidance.

CRITICAL MAPPING: Use the right tool for the right error

Error Type	Tool	What to do
"Forbidden cross-layer import"	Steiger (FSD)	Do NOT use Biome. You must manually move the file using refactor-fsd or change the import pattern.
"Unused export" or "Unresolved import"	Knip	Remove the dead code manually.
"Type X is not assignable to type Y"	TypeScript	Fix the interface/type manually.
"formatting, quotes, or simple unused variables"	Biome	Run npm run lint:fix.

Common Pre-commit Failure Patterns

Error	Fix
import X is defined but never used	Delete the import
variable is assigned but never used	Delete or use the variable
Type 'X' is not assignable to type 'Y'	Fix the type mismatch
Module '"@entities/foo"' has no exported member	Check index.ts exports
Forbidden cross-layer import	Move code to the correct layer
Unused export 'X'	Remove export or add a consumer

Quick Full Fix Sequence

npm run lint:fix          # Auto-fix Biome issues
npm run lint:style:fix    # Auto-fix CSS/SCSS
npm run ts:check          # Identify remaining TS errors (fix manually)
npm run check             # Confirm everything passes