This is a working draft of a checklist to define a "gold standard" for web components that aspire to be as predictable, flexible, reliable, and useful as the standard HTML elements. The fundamental premise of this list is that it should not only be possible to attain that standard; people creating web components for general consumption should aim to meet that standard. These items are focused on designing good components; there are many other good principles for designing good user interfaces at the page or application level which are not listed here.