A system and method for discovering the design time attributes of a component are provided. The invention includes a type descriptor that can access metadata associated with a component and report the metadata to a development tool. The invention further includes a custom type descriptor interface that can be implemented on a component in order to dynamically provide information regarding the component to the type descriptor. The invention further includes a type descriptor filter service interface that can be implemented by the development tool to facilitate filtering of design time information regarding components in order to simulate a run time environment. The invention further comprises methodologies and tools for facilitating application development.