# YAMLCheck

> Validate YAML syntax using python3, lint configs, and convert YAML to JSON. Use when checking syntax, finding errors, or converting formats.

- Skill: `bytesagain/yamlcheck` (Agent Skill, multi-file: 2 files)
- Install (CLI): `npx skillmds@latest add bytesagain/yamlcheck`
- Raw SKILL.md: https://api.skillmd.com/api/skills/bytesagain/yamlcheck/raw
- Safety review: pending (external: skill-scanner PASS, skillspector PASS)
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- Author: bytesagain (https://skillmd.com/u/bytesagain)
- Updated: 2026-09-09
- Page: https://skillmd.com/skills/bytesagain/yamlcheck

---


# YAMLCheck

A real YAML validator and toolkit. Check syntax, convert YAML to JSON, lint for style issues, and list top-level keys. Uses PyYAML when available, falls back to basic parsing when not.

## Commands

| Command | Description |
|---------|-------------|
| `yamlcheck validate <file>` | Validate YAML syntax — reports document count, types, key counts, file size. Falls back to basic tab/colon checks without PyYAML |
| `yamlcheck to-json <file>` | Convert YAML to formatted JSON output. Handles multi-document YAML files |
| `yamlcheck lint <file>` | Check for common style issues: tabs, trailing whitespace, Windows line endings, odd indentation, missing spaces after colons, long lines |
| `yamlcheck keys <file>` | List top-level keys with types and value previews |

## Requirements

- `python3` (required)
- `PyYAML` (optional — enables full parsing; install with `pip3 install pyyaml`)

Without PyYAML, the tool still works but uses basic regex-based checks instead of full YAML parsing.

## Examples

```bash
# Validate a docker-compose file
yamlcheck validate docker-compose.yml

# Convert YAML config to JSON
yamlcheck to-json values.yaml

# Check for style issues
yamlcheck lint playbook.yml

# See what keys are defined
yamlcheck keys config.yaml
```