What is a Web-facing API?

Any css property, DOM property, JS object, event, etc... that are accessible from JavaScript, plugins, and other means from the Web content is considered as Web-facing API.

Checklist for reviewing API implemented by major UAs

• If the spec is before release-candidate stage, CSS property, attribute, element name, etc... must be prefixed with "webkit"
• New API should not conflict with the existing spec
• WebKit's behavior should match that of other UAs unless the spec states otherwise

Checklist for reviewing API NOT implemented by major UAs

• If the spec is before release-candidate stage, CSS property, attribute, element name, etc... must be prefixed with "webkit"
• New API should not expose sensitive information such as visited color and local file name