HTML Validator CLI

html-validator-cli is a command-line interface tool for validating HTML documents against the W3C's validator.w3.org/nu service. It offers a straightforward way to check HTML files, URLs, or raw HTML strings directly from the terminal. The current stable version is 7.0.1. The project demonstrates a moderate release cadence, with several patch and minor updates, and significant major version bumps (6.0.0, 7.0.0) tied to underlying `html-validator` library updates and Node.js engine requirement changes. Key differentiators include support for various output formats (JSON, HTML, text), the ability to ignore specific error messages, and options to validate local files or use a custom validator endpoint. It simplifies HTML validation workflows for developers by integrating directly into shell scripts and CI/CD pipelines without needing a browser or GUI.