# Schema

Each label JSON contains:
- `document_id`: unique invoice id
- `profile`: generation profile name
- `layout_family`: one of the supported invoice layout families
- `difficulty`: `easy`, `medium`, `hard`, or `layout_edge`
- `noise_class`: `clean` or `light_noisy`
- `edge_cases`: list of edge-case tags
- `header_fields`: required invoice header fields with lightweight `value` and `region_hint`
- `line_items_region_hint`: lightweight table-zone hint for the line-item area
- `line_items`: extracted line items with `description`, `quantity`, `unit_price`, `line_total`
