JSON to YAML and YAML to JSON converter / format transcoder / config-file translator / Helm values prepper / Kubernetes manifest converter / GitHub Actions workflow YAML helper / round-trip parser. Auto-detects input format from the first non-whitespace byte ('{'/'[' = JSON, otherwise YAML), parses, and re-serialises in the requested target format. Pretty-print and indent are configurable. Pure parse — no upstream API call, deterministic output.