You create it by starting your markdown document with `---` followed by [[YAML]] encoded attributes and then ending with `---` again. Followed by the regular body of your document.
*`tags` can be specified (as in the example) and are, in effect, another way of adding tags to your page. You can achieve the same result by simply adding hashtags in the body of your document, e.g. `#tag1 #tag2`.
SilverBullet also has the _convention_ of using attributes starting with a `$` for internal use. For instance, the sharing capability uses the `$share` attribute, and `$disableDirectives: true` has the special meaning of disabling [[🔌 Directive]] processing on a page.