# Source connectors

Every source lives in `connectors/<engine>/<source-id>/index.ts` and is declared in `registry.json` (§106).
Adding a marketplace requires only (§197):

1. **metadata** — an entry in `registry.json` (`module` points to the folder, e.g. `"api/scryfall"`);
2. **extraction schema** — the payload shape the connector captures in `crawl()` (typed with Zod);
3. **normalization adapter** — a pure `normalize(raw)` returning canonical `NormalizedRecord[]`;
4. **fixtures** — at least one real captured payload in `data/fixtures/<source-id>/*.json` and a
   `*.test.ts` next to the connector calling `runFixtureSuite`.

The generic pipeline (raw store → normalizer → entity resolution → dedupe → validation → canonical
tables → valuation → indices) then works without changes.

Rules: never invent data, keep source quirks inside the connector, store the source's own dates,
keep the native currency, respect robots/terms/rate limits, and never bypass access controls (§179).

Module contract: `export default (meta: ConnectorMeta) => RareIndexConnector`.

Full guide: `docs/connectors/ADDING_A_CONNECTOR.md` (scaffold with `pnpm connector:new`, adapters for Shopify/
WooCommerce/sitemaps/RSS/PDF/JSON-LD, per-host policies in `domains.json` + `domains.d/`, source catalogue in
`data/sources/entries/`, resumable backfills, health and drift monitoring).