Message types

All frame types

System

Control frames, type: "system", sent in response to connection events and client actions.

{
  "type": "system",
  "event": "ready",
  "ts": 1743512400000
}

Quote

type: "quote" on the *.quotes channels. Every frame carries ts (event time, unix ms) and asset; how numbers are encoded depends on the asset family.

Sizes

bid_size, ask_size and trade size are number | null (string-encoded on the string channels); null means the consolidated feed has no size at that moment.

Snapshot frames

Frames replayed from cache right after subscribe carry "snapshot": true. They appear on stocks, ETFs, indices and commodities; crypto and forex stream continuously and replay only with "view": "full". See Subscriptions.

Futures CFDs

Quotes on futures.quotes add the contract month, its calendar dates, a per-symbol seq and microsecond times. Full reference: Futures CFDs.

Entitlements

A channel can stay silent until coverage is enabled for your account.

{
  "type": "quote",
  "channel": "crypto.quotes",
  "asset": "crypto",
  "symbol": "BTCUSD",
  "bid": "84210.12",
  "ask": "84210.45",
  "bid_size": "1.2",
  "ask_size": "0.8",
  "ts": 1743512400000
}

Trade

type: "trade" on the *.trades channels, with the same encoding rules as quotes. size may be left out or null when the tape has no lot size.

{
  "type": "trade",
  "channel": "crypto.trades",
  "asset": "crypto",
  "symbol": "BTCUSD",
  "price": "84215.42",
  "size": "0.53",
  "ts": 1743512400000
}

Change

type: "change" goes only to a subscribe with "view": "full". It carries the previous close and the move against it, the same values GET /{asset}/snapshot returns. One frame per symbol, sent whenever a value moves.

Numbers

prev_close, change and change_percent are JSON numbers, on every asset class. change and change_percent can be null when no move can be measured. When the previous close rolls to a new day, a frame with all three null takes the old values back until the new ones follow.

ts

Event time of the price the change is measured from: the last trade, or the book while nothing has printed. It is not unique per symbol, so apply change frames in the order they arrive.

channel

The trades channel of the asset class when you subscribed to it, otherwise the quotes channel. The first frame after subscribe is marked "snapshot": true.

{
  "type": "change",
  "channel": "stocks.trades",
  "asset": "stocks",
  "symbol": "US:KO",
  "prev_close": 88.05,
  "change": 0.92,
  "change_percent": 1.0449,
  "ts": 1791818728130
}

Mark

type: "mark" on perpetuals.marks: the composite mark price of a perpetual futures contract, the reference its market uses to value positions, as a string with ts. Full reference: Perpetuals.

Quotes and trades

Perpetuals reuse quote on perpetuals.quotes and trade on perpetuals.trades.

source_count

On every quote and mark: the number of independent sources behind the value.

side

On a trade, buy or sell when the aggressor is known.

{
  "type": "mark",
  "channel": "perpetuals.marks",
  "asset": "perpetuals",
  "symbol": "XAUUSDT",
  "mark_price": "4316.244",
  "source_count": 6,
  "ts": 1789640505932
}

Rate

type: "rate" on bonds.quotes: the latest published government bond yield for a CC:TENOR symbol. Yields are daily observations, not ticks: the current one arrives as a snapshot right after you subscribe, then one frame per new observation, in practice once per business day, so a quiet hour is normal. Numbers are numbers, and the fields match GET /bond/snapshot.

{
  "type": "rate",
  "channel": "bonds.quotes",
  "asset": "bonds",
  "symbol": "US:10Y",
  "rate": 4.79,
  "unit": "percent",
  "date": "2026-09-02",
  "prev_rate": 4.76,
  "prev_date": "2026-09-01",
  "change": 0.03,
  "change_bps": 3,
  "change_percent": 0.6303,
  "ts": 1788307200000,
  "timestamp": 1788307200000
}

Dates

ts and timestamp are the observation date (UTC midnight of date), never the send time. date against prev_date is the interval the change covers.

Change fields

change in percentage points, change_bps in basis points, change_percent relative to prev_rate. The prev_* and change fields are null while only one observation exists.

Snapshot

The frame replayed on subscribe carries "snapshot": true; frames for a new observation do not.

Status

type: "status" on stocks.status: trading halt and resume events for US-listed equities. Subscribe with symbols (US:KO) or, with the market wildcard add-on, US:* for every US listing. Events arrive from subscribe time on and are never replayed, because a cached status may no longer hold.

{
  "type": "status",
  "channel": "stocks.status",
  "asset": "stocks",
  "symbol": "US:KO",
  "status": "halted",
  "reason": "news_pending",
  "ts": 1743512400000
}

reason

Our classification of why: volatility, market_wide, news_pending, news_released, information_requested, regulatory, corporate_action, operational or ipo. Left out when none applies; new values may be added, so decode it tolerantly.

Scope

Halt lifecycle events for US equities only: no auction imbalances, price indications or short sale restriction notices. Both fields are derived classifications, under the data notice that covers every feed.

Agg (OHLCV bar)

type: "agg" on stocks.agg: one settled OHLCV bar per subscribed US symbol and interval, with the letters the REST aggregate routes use (o h l c v), the trade count n and the volume-weighted average price vw. ts is the bar start, never the send time; the frame arrives a few seconds after the window closes, and nothing is replayed on subscribe.

{
  "type": "agg",
  "channel": "stocks.agg",
  "asset": "stocks",
  "symbol": "US:KO",
  "interval": "1m",
  "session": "regular",
  "o": 88.48,
  "h": 88.52,
  "l": 88.46,
  "c": 88.5,
  "v": 41230,
  "n": 312,
  "vw": 88.4917,
  "ts": 1789133400000
}

interval

1m, 5m, 15m, 1h, 4h or 1d, chosen per subscribe (default 1m).

session

pre, regular or post: where in the trading day the bar starts. Intraday bars cover the regular session (09:30 to 16:00 ET, early closes honored) on the /stocks/agg grid unless you subscribe with "session": "extended", which adds pre-market and after-hours bars for 1m, 5m and 15m. The daily bar carries the official open and close, labelled at the session date's UTC midnight like the daily REST bar.

n and vw

Left out when not available for a bar.

The full contract, including when each interval settles, is in Stocks: OHLCV bars over WebSocket.

etfs.agg sends the same frame for US-listed ETFs, with "channel": "etfs.agg", "asset": "etfs" and the ETF symbol as /etfs/symbols lists it. See ETFs: OHLCV bars over WebSocket.

Error

type: "error" when a client action fails validation or a limit is breached after the connection is open. Subscribe failures use event: "subscribe_failed" (or subscribe_partial_failed). There is no details object; rejected symbols appear in rejected when present.

{
  "type": "error",
  "event": "subscribe_failed",
  "code": "SYMBOL_LIMIT_EXCEEDED",
  "message": "rate limit exceeded"
}

Every error code is listed on Errors & troubleshooting.