# API Doc Entity
### Scope
- **Purpose**: Document the public interface exposed by `derive_tools_meta`.
- **Responsibility**: Master index for all API doc instances in this crate.
- **In Scope**: Instance 001 — derive macro names, applicability, and feature flags.
- **Out of Scope**: Behavioral rationale — see `feature/` and `invariant/` instances.
### Overview Table
| 001 | [Derive API](001_derive_api.md) | Public derive macro interface — names, applicability, and feature flags | ✅ |