Document code purposefully

High-quality code documentation improves maintainability and helps other developers understand your intentions. Follow these practices:

1. Use appropriate JSDoc annotations to indicate API visibility and status:

   /** @internal */
   hostname: Hostname
      
   /**
    * @deprecated Use `createIdResolver` from `vite` instead.
    */
   

2. Structure API documentation logically by describing functionality first, then providing implementation details or deprecation notices: ```typescript /**
   • Create an internal resolver to be used in special scenarios, e.g.
   • optimizer & handling css @imports. *
   • This API is deprecated. It only works for the client and ssr
   • environments. The aliasOnly option is also not being used anymore.
   • Plugins should move to createIdResolver(environment.config) instead. */ ```
3. Add explanatory comments for non-obvious code decisions to explain the “why” behind implementation choices:

   // only limit to these extensions because:
   // - for the `@import`/`@use`s written in file loaded by `load` function,
   //   the `canonicalize` function of that `importer` is called first
   // - the `load` function of an importer is only called for the importer
   //   that returned a non-null result from its `canonicalize` function
   (resolved.endsWith('.css') || resolved.endsWith('.scss') || resolved.endsWith('.sass'))
   

4. Keep documentation updated when implementing changes, especially for deprecated features. Explicitly indicate migration paths and alternatives when deprecating functionality.