> ## Documentation Index
> Fetch the complete documentation index at: https://docs.testnet.dev.adipredictstreet.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Orderbook

> Snapshot + incremental update formats.

## Snapshot

```http theme={null}
GET /api/markets/{symbol}/orderbook?outcome=0&depth=20
```

```json theme={null}
{
  "marketId": "UAE-CUP-FINAL-20260425",
  "outcome": "0",
  "bids": [
    { "price": "0.52", "quantity": "240" },
    { "price": "0.51", "quantity": "180" }
  ],
  "asks": [
    { "price": "0.55", "quantity": "210" },
    { "price": "0.56", "quantity": "160" }
  ],
  "seq": 128471,
  "hash": "9f3b1c0a2d4e5f60",
  "ts": "2026-04-22T10:31:05.124Z"
}
```

Levels are aggregated — one entry per unique price, summed across
all resting orders at that price.

## Live updates

For real-time book updates use the WebSocket `orderbook` channel.
See [WebSocket messages](/concepts/websocket/messages).

The snapshot carries a `seq` field; subsequent WS deltas carry an
incrementing `seq`. If your local copy drifts, request a fresh
snapshot.

## Reconciliation with the WebSocket feed

The `hash` field is a canonical 16-hex SHA-256 prefix over the
`(bids, asks)` pair — price + quantity only, computed by both
core-api (on this response) and ws-gateway (on `book_snapshot` and
`book_update` envelopes). For the same logical book state the two
sides produce identical hashes.

Typical reconciliation flow:

1. Open the WebSocket and subscribe to `token_book` for the
   tokenId you care about.
2. Buffer incoming `book_snapshot` / `book_update` frames keyed by
   their envelope `seq`.
3. Call `GET /api/markets/{symbol}/orderbook` and read the response
   `hash`.
4. Walk the buffered WS frames to find one with a matching `hash`
   — that `seq` is your alignment point; drop earlier frames, apply
   later ones onto the REST snapshot.
5. From there each `book_update` you apply must produce the same
   `hash` as the envelope. If they ever diverge, issue
   [`get_book_snapshot`](/concepts/websocket/subscriptions#snapshot-refresh-get_book_snapshot)
   to force a fresh server-side snapshot and restart alignment.

The hash domain is identical between REST and WS by construction —
`count` is excluded from the hash on both sides, so an aggregated
REST response (no count) and a `book_snapshot.data` (with count)
produce the same hash for the same `(bids, asks)`.

## Cross-reference

The orderbook is the matcher's view of resting orders. For your own
orders, always cross-reference with `GET /api/me/orders/open` — that
is authoritative from PG.