Exchanges

Canonical names live in apis.venue and as the first segment of a universal ticker: Venue_Category_SYMBOL. A venue is one connection with one credential. Tickers and deploy YAML: Write & publish. Feed hooks: Hooks.

Names are CamelCase with no underscore (GateFutures, never gate_futures). The middle segment is the category the venue actually trades (Spot, Perp, Inverse, Future). A name that is not in this registry is refused when the credential is stored — not later, at deploy.

Registry

Name	Label	Categories	Credential	Example
Paper	Paper	Spot	Simulated — no real money	Paper_Spot_BTCUSDT
Gate	Gate Spot	Spot	HMAC	Gate_Spot_BTCUSDT
GateFutures	Gate USD-M Futures	Perp	HMAC	GateFutures_Perp_BTCUSDT
Binance	Binance Spot	Spot	Ed25519	Binance_Spot_BTCUSDT
BinanceUM	Binance USD-M Futures	Perp, Future	Ed25519	BinanceUM_Perp_BTCUSDT
BinanceCM	Binance COIN-M Futures	Inverse, Future	Ed25519	BinanceCM_Inverse_BTCUSD
Bybit	Bybit	Spot, Perp	HMAC	Bybit_Perp_BTCUSDT
Okx	OKX	Spot, Perp	HMAC + passphrase	Okx_Perp_BTCUSDT
Bitget	Bitget	Spot, Perp	HMAC + passphrase	Bitget_Spot_BTCUSDT

Spelling is load-bearing: the code name is Okx, not OKX or Okex. There is no HTX, Deribit, or KuCoin venue.

Classic vs unified

Classic — one market per credential. Gate spot and GateFutures are two venues: separate host, wallet, and API key. Binance spot, USD-M (BinanceUM), and COIN-M (BinanceCM) are three venues. Binance issues one key string for all three planes; uniqueness is (venue, api_key). Store the key on the venue you will trade. This adapter signs Binance over WebSocket session.logon — Ed25519 only; HMAC is refused when the credential is stored.

Unified — one credential, several books. Bybit, Okx, and Bitget sign once. The category is the instrument's property: Bybit_Spot_BTCUSDT and Bybit_Perp_BTCUSDT are two tickers on one venue. Okx and Bitget need a passphrase. Bitget USDC-M is still Perp — the settle coin is in the symbol (Bitget_Perp_BTCUSDC ≠ Bitget_Perp_BTCUSDT). Classic per-market wallets on those brands are not modelled.

A unified venue has no default category. Name the book in the ticker.

Market data

A subscribe the venue does not serve is refused at attach — the connector has no stream_*, or the method refuses that category. A query it cannot answer comes back MD_VENUE_UNSUPPORTED_READ on the on_fetch_* result (or None from mds.fetch_* if it never left).

Every live venue serves ticker, trade, and orderbook. bestquote and kline_{interval} are on every real venue; paper has neither.

Topic	Who serves it
aggtrade	Binance, BinanceUM, BinanceCM. Gate, GateFutures, Bybit, Okx, Bitget, and Paper refuse.
liquidation	GateFutures; BinanceUM / BinanceCM (sampled — largest per symbol per second); Bybit / Okx / Bitget perp. Spot and paper refuse.
funding_rate	Perp books (BinanceCM: Inverse). Spot, paper, and dated Future refuse.
open_interest	GateFutures; Bybit / Okx / Bitget perp. BinanceUM / BinanceCM have no stream — use mds.fetch_open_interest. Spot and paper refuse.

funding_rate is the still-moving prediction for the next settlement, not a locked period constant. open_interest.qty is one side, in base on every linear book; BinanceCM reports contracts, like the rest of that venue's public sizes.

On Bybit, GateFutures, and Bitget, funding and OI ride the ticker wire. A late joiner is silent until the next rate- or size-bearing delta — the pump is not REST-filled.

Queries

mds call	Who answers
fetch_klines / fetch_order_book / fetch_best_quote	Every real venue. Paper has no fetch reader.
fetch_funding_history	Same books as the live funding feed. Settled rows, oldest first. Spot, paper, and dated Future refuse.
fetch_open_interest	Contract venues including BinanceUM / BinanceCM. Snapshot of now, not a bucketed series. Spot and paper refuse.

Which candle windows a venue serves is the venue's business. An interval it does not have comes back MD_INTERVAL_NOT_SUPPORTED on the result. Interval spelling stays canonical (1m, 4h, 1mo).

Other caveats

• Paper — same ticker shape and OMS path, no real money. No candles, no aggtrade, no funding/OI, no mds.fetch_*.
• Gate — no aggregated tape on spot or futures. GateFutures sizes are converted to base via contract_size.
• BinanceUM / BinanceCM — no raw tape: trade and aggtrade both read @aggTrade (ids are aggregate ids on both). Liquidations are a sample, not a full record. OI is fetch-only; a series there is a timer plus fetch_open_interest, not a subscribe.
• BinanceCM — inverse perpetual is BinanceCM_Inverse_BTCUSD, never …_Perp_BTCUSD. Book, tape, liquidations, and OI qty stay in contracts. Example symbol is BTCUSD, not BTCUSDT.
• Bybit — liquidations and funding are perp. OI is perp (this venue does not list Future or options).
• Okx / Bitget — passphrase required. Funding, OI, and liquidations are perp; spot refuses those topics at attach.

Private TD events (on_position_update, …) are account-wide on the attached api_id. Contract venues report positions; spot never calls on_position_update. Filter with self.owns(cid): Hooks.

Next

Strategy hooks: Hooks. Authoring a deploy: Write & publish.