Market Info Websocket

Public WebSocket channels for real-time market data. No SIWE authentication required, but the upgrade requires an _idx_session cookie — see Session Cookie.

Connection

wss://api.t.synchronicity.xyz/indexer-ws/ws

Prime the cookie with GET /indexer/session, then open the upgrade with Cookie: _idx_session=…. A missing or invalid cookie returns 403 at upgrade time; the 403 response carries a fresh cookie in Set-Cookie — capture it and retry. See Session Cookie — WebSocket for the full handshake.

All messages are JSON.

Errors

All errors use the format:

{
  "type": "error",
  "message": "descriptive error message"
}

Channels

orderbook_depth

Orderbook price levels. No authentication required.

Subscribe:

{
  "action": "subscribe",
  "channel": "orderbook_depth",
  "orderbook_ids": [123, 456]
}

Snapshot: None. Updates are only sent when a batch is cleared.

Update:

{
  "type": "orderbook_depth_updated",
  "orderbook_id": 123,
  "depth": {
    "orderbook_id": 123,
    "bids": [{ "price": "50000.00", "volume": "10.5" }],
    "asks": [{ "price": "50001.00", "volume": "15.0" }],
    "midpoint": "50000.50",
    "spread": "1.00",
    "timestamp": 1704067200000
  }
}

PriceLevel Object:

This is a full snapshot replacement, not a delta. Replace the entire order book depth with this data.

orderbook_depth_pre_clearance

Orderbook depth snapshot captured right before the FBA (Frequent Batch Auction) is run — this is the exact book state that the clearing algorithm operates on. Only sent when bids and asks cross; if no cross occurs in a batch cycle, no snapshot is emitted. Useful for understanding how clear_price was calculated and for visualising FBA behaviour. No authentication required.

When subscribed to both channels, orderbook_depth_pre_clearance is always delivered before orderbook_depth_updated within the same batch cycle.

Subscribe:

{
  "action": "subscribe",
  "channel": "orderbook_depth_pre_clearance",
  "orderbook_ids": [123, 456]
}

Unsubscribe:

{
  "action": "unsubscribe",
  "channel": "orderbook_depth_pre_clearance",
  "orderbook_ids": [123, 456]
}

Snapshot: None. Sent only when a batch has fills.

Update:

{
  "type": "orderbook_depth_pre_clearance",
  "orderbook_id": 123,
  "depth": {
    "orderbook_id": 123,
    "bids": [{ "price": "50000.00", "volume": "10.5" }],
    "asks": [{ "price": "50001.00", "volume": "15.0" }],
    "midpoint": "50000.50",  // ignore — not meaningful for crossed bids/asks
    "spread": "1.00",        // ignore — not meaningful for crossed bids/asks
    "timestamp": 1704067200000
  },
  "clear_price": "50000.75",
  "clear_volume": "5.0"
}

Same shape as orderbook_depth_updated — see the field table in orderbook_depth above — plus two additional fields:

orderbook_bbo

Best bid and offer (top-of-book). Lightweight alternative to orderbook_depth — sends only the best bid and best ask with their volumes. No authentication required.

Subscribe:

{
  "action": "subscribe",
  "channel": "orderbook_bbo",
  "orderbook_ids": [123, 456]
}

Snapshot: None. Updates are only sent when a batch is cleared.

Update:

{
  "type": "bbo_updated",
  "orderbook_id": 123,
  "bid": { "price": "50000.00", "volume": "10.5" },
  "ask": { "price": "50001.00", "volume": "15.0" },
  "timestamp": 1704067200000
}

bid and ask use the same PriceLevel object as orderbook_depth (price and volume as decimal strings). Either side can be null if that side of the book is empty.

orderbook_trades

Batch trade notifications. No authentication required.

Subscribe:

{
  "action": "subscribe",
  "channel": "orderbook_trades",
  "orderbook_ids": [123, 456]
}

Snapshot: None.

Update:

{
  "type": "batch_traded",
  "orderbook_id": 123,
  "price": "50000.00",
  "size": "50.5",
  "timestamp": 1704067200000
}

Sent once per batch when the batch is cleared.

orderbook_context

Mark price, index price, 24h stats, funding, and open interest. No authentication required.

Subscribe:

{
  "action": "subscribe",
  "channel": "orderbook_context",
  "orderbook_ids": [123, 456]
}

Snapshot: Sent on subscribe.

Update:

{
  "type": "orderbook_context_updated",
  "orderbook_id": 123,
  "mark_price": "50000.00",
  "index_price": "50010.50",
  "price_24h_ago": "48000.00",
  "change_24h": "4.17",
  "volume_24h": "1000000.50",
  "open_interest": "5000.0",
  "funding_rate": "0.0001"
}

candles

Candlestick OHLCV data. No authentication required.

Subscribe:

{
  "action": "subscribe",
  "channel": "candles",
  "orderbook_ids": [123],
  "intervals": ["1m", "5m", "1h"]
}

Valid intervals: 1m, 3m, 5m, 15m, 30m, 1h, 2h, 4h, 8h, 12h, 1d, 3d, 1w, 1M

Snapshot: None.

Update:

{
  "type": "candle_updated",
  "t": 1704067200000,
  "T": 1704067260000,
  "s": "BTC/USD",
  "i": "1m",
  "o": "50000.00",
  "c": "50100.50",
  "h": "50150.00",
  "l": "49950.00",
  "v": "100.5",
  "n": 50
}

all_mids

Mid-prices for all orderbooks, broadcast every 150ms. No authentication required.

Subscribe:

{
  "action": "subscribe",
  "channel": "all_mids"
}

No orderbook_ids parameter — this is a global channel that covers all orderbooks.

Snapshot: None.

Update:

{
  "type": "all_mids_updated",
  "mids": {
    "1": "50000.50",
    "2": "3200.25",
    "3": "150.123"
  }
}

Mid-prices are calculated as (bestBid + bestAsk) / 2 and cached on each batch clear. The channel broadcasts the latest cached values every 150ms.

Snapshot Summary

Data Types

• All numeric values (prices, volumes, balances) are strings to preserve precision.
• Timestamps are milliseconds (Unix epoch).
• is_bid: true = buy, false = sell.
• orderbook_id: uint64.