This is a first pass at generating responsive wireframes from simple markdown files. I love creating notes in markdown and creating an outline of content for a page in a text file is standard procedure. It is a simple matter to convert markdown to HTML so why not include some blocks to show basic page layout and have it be responsive.
With this short python script and CSS file, you can convert a folder of markdown files into HTML files with blocks or rows of blocks that are in a column on mobile.
This page goes into more detail: index.html
It was created from this markdown file