* network interceptors return.
   */
  internal var interceptorScopedExchange: Exchange? = null
    private set

  // These properties are guarded by `this`. They are typically only accessed by the thread executing
  // the call, but they may be accessed by other threads for duplex requests.

  /** True if this call still has a request body open. */
  private var requestBodyOpen = false

- **Bean introspection** - The comprehensive `BeanDesc` system provides metadata about JavaBeans, accessed through `BeanDescFactory.getBeanDesc(Class)`
- **Type safety** - Extensive use of generics and null-safe operations throughout the API