qlty-check

Qlty Code Quality

Universal code quality tool supporting 70+ linters for 40+ languages via qlty CLI.

When to Use

• Check code for linting issues before commit/handoff
• Auto-fix formatting and style issues
• Calculate code metrics (complexity, duplication)
• Find code smells

Quick Reference

# Check changed files with auto-fix
uv run python -m runtime.harness scripts/qlty_check.py --fix

# Check all files
uv run python -m runtime.harness scripts/qlty_check.py --all

Format files

uv run python -m runtime.harness scripts/qlty_check.py --fmt

Get metrics

uv run python -m runtime.harness scripts/qlty_check.py --metrics

Find code smells

uv run python -m runtime.harness scripts/qlty_check.py --smells

## Parameters

| Parameter | Description |
|-----------|-------------|
| `--check` | Run linters (default) |
| `--fix` | Auto-fix issues |
| `--all` | Process all files, not just changed |
| `--fmt` | Format files instead |
| `--metrics` | Calculate code metrics |
| `--smells` | Find code smells |
| `--paths` | Specific files/directories |
| `--level` | Min issue level: note/low/medium/high |
| `--cwd` | Working directory |
| `--init` | Initialize qlty in a repo |
| `--plugins` | List available plugins |

## Common Workflows

### After Implementation
```bash
# Auto-fix what's possible, see what remains
uv run python -m runtime.harness scripts/qlty_check.py --fix

Quality Report

# Get metrics for changed code
uv run python -m runtime.harness scripts/qlty_check.py --metrics

# Find complexity hotspots
uv run python -m runtime.harness scripts/qlty_check.py --smells

Initialize in New Repo

uv run python -m runtime.harness scripts/qlty_check.py --init --cwd /path/to/repo

Direct CLI (if qlty installed)

# Check changed files
qlty check

# Auto-fix
qlty check --fix

# JSON output
qlty check --json

# Format
qlty fmt

Requirements

• qlty CLI: https://github.com/qltysh/qlty
• MCP server: servers/qlty/server.py wraps CLI
• Config: .qlty/qlty.toml in repo (run qlty init first)

vs Other Tools

Tool	Use Case
qlty	Unified linting, formatting, metrics for any language
ast-grep	Structural code patterns and refactoring
morph	Fast text search