# Riff HIERARCHY_SCREEN contract — registry

> **Status:** Adopted and normative for HIERARCHY_SCREEN only\
> **Authority:** Registered by [Riff system requirements](requirements.md). System-wide requirements
> control catalog membership, classification, queues, storage, safety and shared UI rules.

This page is a bounded registry. The linked children own the detailed requirements.

## Sections

- [Scope and shared implementation](hierarchy-screen-scope-and-shared-implementation.md)
- [ROW_ACTIONS and audiobook classification](hierarchy-screen-row-actions-and-audiobook-classification.md)