# Contract Delta: 008 Pricing Awareness and Market Data

> For the complete documentation index, see [llms.txt](https://deploy-preview-472--lucky-concha-f3599f.netlify.app/llms.txt).

Parent state: `007-observability-lgtm-compose`

## REST/OpenAPI Changes

*   `trade-service` request/response schema extends `TradeOrder` with `price`.
*   `position-service` payloads include `averageCostBasis` in positions and `price` in trades.
*   New local service endpoint:
    *   `price-publisher`: `GET /prices`, `GET /prices/{ticker}`, `GET /health`.
    *   `GET /prices` is the canonical multi-symbol bootstrap path (all symbols by default, optionally filtered by request parameters when provided by implementation).
    *   `price-publisher /health` includes active publish cadence config (`minMs`, `maxMs`, `ratio`).

## Event Contract Changes

*   Existing account-scoped topics remain:
    *   `/accounts/<accountId>/trades`
    *   `/accounts/<accountId>/positions`
*   New market data topic family:
    *   `pricing.<TICKER>`

Expected pricing payload:

```json
{  "ticker": "IBM",  "price": 187.245,  "openPrice": 186.000,  "closePrice": 187.400,  "asOf": "2026-03-31T11:00:00.000Z",  "source": "snapshot"}
```

`asOf` is a server-assigned timestamp and is required for both snapshot REST responses and stream (`pricing.<TICKER>`) events so clients can safely pick the freshest update.

## Reference Data Symbol Contract Notes

*   State `008` normalizes legacy `FB` symbol to `META` for returned stock identifiers.
*   Runtime supported symbol set is expected to match between `reference-data` and `price-publisher`.