Screenshots for Each Pen
Large Image Preview
https://codepen.io/USERNAME/pen/SLUG/image/large.png
Small Image Preview
https://codepen.io/USERNAME/pen/SLUG/image/small.png
Editor Layout
These can be combined.
Layout Type
http://codepen.io/USERNAME/pen/SLUG/left/
http://codepen.io/USERNAME/pen/SLUG/right/
http://codepen.io/USERNAME/pen/SLUG/top/
Open/Closed Editors
http://codepen.io/USERNAME/pen/SLUG/?editors=1010
In the four digit number (e.g. 1010), 1 is open, 0 is closed. The first digit is the HTML editor, second is the CSS editor, third is the JavaScript editor, and the fourth is the console.