omni-article-markdown is a CLI tool and library that converts web articles from various sources into clean Markdown format. It employs a modular pipeline architecture: Reader fetches HTML (using requests or Playwright for JavaScript-heavy sites), Extractor isolates article content by removing boilerplate and ads, and Parser converts the cleaned HTML to Markdown with support for code blocks, tables, math equations, and GitHub Gists. The system uses a plugin-based architecture where site-specific readers and extractors are automatically discovered and loaded, allowing easy extension for new websites. Key features include SSL verification control, cookie persistence for sites requiring authentication (like Zhihu), and flexible output options (stdout or file saving).