WebSocket Protocol

Event Contracts API WebSocket message format and subscription flow.

Messages are JSON objects. The request timestamp t must be within 60 seconds of server time, and id must be a string or integer.

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Subscribe

{
  "t": 1720000000123,
  "id": "req-1",
  "op": "subscribe",
  "ch": "ec.depth",
  "payload": {
    "items": [
      {
        "token_id": "ge_token-yes",
        "level": 20
      }
    ]
  }
}

Use op: "unsubscribe" with the same channel and payload to remove a subscription. Private channels also include an auth object. Private channels support {"all": true}; public channels require items.

​

Acknowledgements

Success:

{
  "t": 1720000000124,
  "id": "req-1",
  "trace_id": "trace-1",
  "op": "subscribe",
  "ch": "ec.depth",
  "err": null,
  "result": {
    "status": "success"
  }
}

Failure:

{
  "t": 1720000000124,
  "id": "req-1",
  "trace_id": "trace-1",
  "op": "subscribe",
  "ch": "ec.depth",
  "err": {
    "code": 2,
    "msg": "invalid depth item"
  },
  "result": {
    "status": "fail"
  }
}

​

Updates and snapshots

Data messages use type: "snapshot" for cached initial state and type: "update" for later events. They contain ch, err: null, and a channel-specific result.

A connection supports up to 100 subscription items per request and up to 10,000 active subscriptions. On reconnect, resubscribe and use REST endpoints to recover account state for private channels.