The checked MetService public marine/surf response exposes an HTML application shell but no stable named-spot payload, timestamp schema, units, or update contract; no forecast is scraped.
South Island Waves identifies a Kaikoura buoy, but its checked public list and buoy-data response were empty. The Banks Peninsula buoy is 150+ km south and is not substituted for Mangamaunu.
LINZ is retained as an official tide-table reference, but no spot-specific station, distance, chart datum, timezone, and current response is connected.