Methodology

rewa.au publishes one page per Western Australian cadastral parcel (1,720,781 parcels). The page, the JSON object index.json beside each page and the get_parcel MCP tool are projections of one parcel object, built by one deterministic engine.

Deterministic engine

• Every value is read from a named register by the parcel's slip_land_id. Nothing is estimated or synthesised.
• A fact is shown only when its value is present. A missing fact is omitted, never guessed.
• Overlay statuses (AFFECTS / DOES_NOT_AFFECT) are stated only for open-licensed statewide layers: bushfire. A layer that does not cover a parcel is never reported as clear.
• A link to an official source is shown on every page or on none: a link that appeared only on parcels inside a restricted layer would disclose that layer.
• The opening paragraph may be written by a language model from the facts on the page only. A validator rejects any number that is not in the facts, and a fixed template is used otherwise. The model never adds a fact.

Licence tiers

• FREE_AUTO: open-licensed data, published with its attribution.
• DEEP_LINK: restricted data (registered boundary and area, tenure, planning zone and R-Code, contaminated-sites status, wetland category, flood mapping). The page links to the official source and never shows the value.
• REPORT_ONLY: title, ownership and dealings, heritage listing and utilities infrastructure. Not published on the free pages.
• No coordinates or measurements derived from the Landgate cadastral boundary are published; a map position is given only from a G-NAF address geocode.

Provenance on every fact

• source_agency and source_dataset: who published the data, and which dataset.
• as_at: when the source says the fact was true.
• retrieved_at: when rewa.au fetched it.
• method: direct, spatial_intersection or clip_to_title.
• publish_tier and attribution: the licence tier and the attribution string.
• A fact missing any of these is not published.
• Every page and its index.json come from one release; the object names it in snapshot_id.

Not a valuation

rewa.au is a research signal. It does not value property, give financial advice, or state who owns a parcel. Confirm every fact with the official source before relying on it.