AsyncAPI channel · Alpaca
· Alpaca Market Data Streaming (WebSocket)
/v1beta3/crypto/us
Crypto market data stream. Same auth/subscribe handshake as the stock stream, plus an `orderbooks` channel carrying Level 2 book snapshots (first message per symbol) and incremental updates.
Channel address
/v1beta3/crypto/us
Operations
publish
sendCryptoControlMessage
Send a crypto control message (auth, subscribe, unsubscribe).
subscribe
receiveCryptoDataMessages
Receive streamed crypto market data.
Messages
AuthMessage
First client message; authenticates the connection.
Content-Type:
application/jsonSubscribeMessage
Subscribe to one or more channels per symbol or with a wildcard.
Content-Type:
application/jsonUnsubscribeMessage
Remove channel subscriptions.
Content-Type:
application/jsonSuccessMessage
Server acknowledgement (connected / authenticated).
Content-Type:
application/jsonErrorMessage
Server error (bad auth, invalid subscription, connection limit, etc.).
Content-Type:
application/jsonSubscriptionMessage
Server echo of the current active subscriptions after a subscribe/unsubscribe.
Content-Type:
application/jsonTradeMessage
A single executed trade.
Content-Type:
application/jsonQuoteMessage
A national best bid/offer (or crypto) quote.
Content-Type:
application/jsonBarMessage
An OHLCV aggregate bar (minute, daily, or updated).
Content-Type:
application/jsonOrderbookMessage
A Level 2 orderbook snapshot or update (crypto stream only).
Content-Type:
application/jsonAbout AsyncAPI
The AsyncAPI specification describes event-driven APIs the way OpenAPI describes request/response APIs. A channel is the named pipe — a webhook URL, a Kafka topic, a WebSocket route, an MQTT subject — that producers and consumers publish or subscribe to. Each channel carries one or more messages with structured payloads, and an operation declares whether a given party sends or receives on that channel.
Browse every event-driven channel on the APIs.io network or compare with the broader Agent Skill and MCP server surfaces of the same providers.