Protocol overview

Tessium Streaming API v1 uses JSON messages over one WebSocket connection. One connection can carry multiple independent subscriptions.

Endpoint

wss://api.tessium.dev/stream?key=YOUR_API_KEY

You can also authenticate with the first WebSocket message when keeping the key out of the URL is more convenient:

{ "op": "auth", "key": "tsk_live_..." }

Frame kinds

op	Direction	Purpose
auth	client → server	Authenticate when the key is not in the URL
subscribe	client → server	Open a stream subscription
unsubscribe	client → server	Stop a subscription
ping	client → server	Application-level connection check
ack	server → client	Confirm a command and return the subscription id
pong	server → client	Reply to an application-level ping
event	server → client	Deliver a stream event
error	server → client	Reject a command or report a failure
notice	server → client	Report non-fatal stream state

See Frames for complete command envelopes, Cursor & replay for reconnect behavior, Detail levels for payload tiers, and Errors & notices for every machine-readable code.

Delivery model

• Only successful Solana transactions are streamed.
• Every non-candle event has a common transaction envelope.
• blockTime can be null while block time is not yet available; Tessium does not hold the event back while waiting for it.
• A token subscription and a wallet subscription can both emit an event for the same trade. They are separate subscriptions, not duplicates.
• Client messages are limited to 64 KB.

Protocol version: v1. Reference snapshot: 31 July 2026.