WebSocket API

Endpoint

wss://api.vatic.trading/ws

No authentication required. Connect once and subscribe to any supported asset / stream combination.

Available streams

The WebSocket currently supports two real-time streams:

Stream	Subscribe with	What you receive
Vatic target prices	`{"type":"subscribe","asset":"btc","marketTypes":["5min","15min"]}`	`window_open` events at each Polymarket/Vatic market boundary
Hyperliquid mark prices	`{"type":"subscribe","channel":"hyperliquid_mark_price","asset":"btc"}`	`hyperliquid_mark_price` snapshots and live updates for the underlying perp mark price

Why WebSocket over polling?

REST polling at window boundaries causes two problems:

502 errors — Chainlink/Binance takes 1–5s to publish a price after a window opens. Polling at :00 means your request arrives before the price exists.
Rate limits — Hammering the endpoint while waiting burns your 120 req/min budget instantly.

The WebSocket absorbs the publish lag server-side, retries the upstream fetch automatically, and pushes the resolved price to all subscribers the instant it’s ready. For Hyperliquid, it also gives you live access to the underlying markPrice that matters for prediction-market settlement.

Market types

Type	Boundary	Price source
`5min`	Every 5 minutes	Chainlink Data Streams
`15min`	Every 15 minutes	Chainlink Data Streams
`1hour`	Top of every hour	Binance aggTrades
`4hour`	00:00, 04:00, 08:00, 12:00, 16:00, 20:00 ET	Binance aggTrades
`daily`	Midnight ET	Binance aggTrades

Supported assets: btc, eth, sol, xrp, hype, doge, bnb

Connection flow

1. Connect

On connect the server immediately sends a connected event:

{
  "event": "connected",
  "supportedAssets": ["btc", "eth", "sol", "xrp", "hype", "doge", "bnb"],
  "supportedMarketTypes": ["5min", "15min", "1hour", "4hour", "daily"],
  "supportedChannels": ["hyperliquid_mark_price"],
  "usage": [
    "Send {\"type\":\"subscribe\",\"asset\":\"btc\",\"marketTypes\":[\"5min\",\"15min\"]}",
    "Send {\"type\":\"subscribe\",\"channel\":\"hyperliquid_mark_price\",\"asset\":\"btc\"}"
  ]
}

Vatic target prices

Send a JSON message to subscribe to one asset across one or more market types:

{
  "type": "subscribe",
  "asset": "btc",
  "marketTypes": ["5min", "15min"]
}

Field	Type	Description
`type`	`"subscribe"`	Required.
`asset`	string	One of the supported asset symbols.
`marketTypes`	string[]	One or more market types. Omit to subscribe to all five.

The server confirms with a subscribed event and immediately pushes a window_open snapshot for the current window of each subscribed type — so you always have the latest price on connect, without waiting for the next boundary.

{ "event": "subscribed", "asset": "btc", "marketTypes": ["5min", "15min"] }

Hyperliquid mark price

Send a JSON message to subscribe to the underlying perp mark-price stream:

{
  "type": "subscribe",
  "channel": "hyperliquid_mark_price",
  "asset": "btc"
}

Field	Type	Description
`type`	`"subscribe"`	Required.
`channel`	`"hyperliquid_mark_price"`	Required for the Hyperliquid mark-price stream.
`asset`	string	One of the supported asset symbols.

The server confirms with:

{ "event": "subscribed", "channel": "hyperliquid_mark_price", "asset": "btc" }

It then immediately pushes a snapshot:

{
  "event": "hyperliquid_mark_price",
  "channel": "hyperliquid_mark_price",
  "asset": "btc",
  "coin": "BTC",
  "source": "hyperliquid",
  "markPrice": 78669,
  "oraclePrice": 78700,
  "midPrice": 78669.5,
  "prevDayPx": 78333,
  "change24h": 0.4289379954808319,
  "openInterest": 29626.19272,
  "funding": 0.0000058782,
  "volume": 921508494.6523755,
  "observedAt": "2026-05-03T13:38:56.147Z",
  "snapshot": true
}

After the snapshot, the server keeps broadcasting updates whenever the upstream Hyperliquid perp context changes.

3. Receive price events

At every window boundary the server pushes a window_open event:

{
  "event": "window_open",
  "asset": "btc",
  "marketType": "5min",
  "windowStart": 1744027500,
  "windowStartIso": "2025-04-07T12:05:00.000Z",
  "price": 82450.75,
  "source": "chainlink"
}

The initial snapshot after subscribe includes "snapshot": true. If the upstream price fetch fails after all retries, you receive window_open_error instead:

{
  "event": "window_open_error",
  "asset": "btc",
  "marketType": "5min",
  "windowStart": 1744027500,
  "windowStartIso": "2025-04-07T12:05:00.000Z",
  "error": "Price unavailable — upstream fetch failed after retries"
}

4. Unsubscribe

{ "type": "unsubscribe" }

Removes all subscriptions for the current connection.

Heartbeat

The server sends a WebSocket ping every 30 seconds. If your client does not respond with a pong, the connection is terminated. Most WebSocket libraries handle this automatically.

Examples

Node.js

import WebSocket from 'ws';

function connect() {
  const ws = new WebSocket('wss://api.vatic.trading/ws');

  ws.on('open', () => console.log('connected'));

  ws.on('message', (raw) => {
    const text = typeof raw === 'string' ? raw : raw.toString();
    const msg = JSON.parse(text);

    if (msg.event === 'connected') {
      ws.send(JSON.stringify({
        type: 'subscribe',
        asset: 'btc',
        marketTypes: ['5min', '15min'],
      }));
    }

    if (msg.event === 'window_open') {
      const label = msg.snapshot ? 'snapshot' : 'LIVE';
      console.log(`[${label}] ${msg.asset} ${msg.marketType} — $${msg.price} (${msg.windowStartIso})`);
    }
  });

  ws.on('close', () => {
    console.log('disconnected, reconnecting in 3s...');
    setTimeout(connect, 3000);
  });

  ws.on('error', (err) => console.error('ws error:', err.message));
}

connect();

TypeScript — Hyperliquid mark price

import WebSocket, { type RawData } from 'ws';

function connect() {
  const ws = new WebSocket('wss://api.vatic.trading/ws');

  ws.on('message', (raw: RawData) => {
    const text = typeof raw === 'string' ? raw : raw.toString();
    const msg = JSON.parse(text);

    if (msg.event === 'connected') {
      ws.send(JSON.stringify({
        type: 'subscribe',
        channel: 'hyperliquid_mark_price',
        asset: 'btc',
      }));
    }

    if (msg.event === 'hyperliquid_mark_price') {
      const label = msg.snapshot ? 'snapshot' : 'LIVE';
      console.log(
        `[${label}] ${msg.asset} mark=${msg.markPrice} oracle=${msg.oraclePrice} funding=${msg.funding} at ${msg.observedAt}`
      );
    }
  });

  ws.on('close', () => setTimeout(connect, 3000));
}

connect();

Python

import asyncio, json
import websockets

async def connect():
    uri = "wss://api.vatic.trading/ws"
    while True:
        try:
            async with websockets.connect(uri, ping_interval=30) as ws:
                print("connected")
                async for raw in ws:
                    msg = json.loads(raw)

                    if msg["event"] == "connected":
                        await ws.send(json.dumps({
                            "type": "subscribe",
                            "asset": "btc",
                            "marketTypes": ["5min", "15min"],
                        }))

                    elif msg["event"] == "window_open":
                        label = "snapshot" if msg.get("snapshot") else "LIVE"
                        print(f"[{label}] {msg['asset']} {msg['marketType']} — ${msg['price']} ({msg['windowStartIso']})")

        except Exception as e:
            print(f"disconnected ({e}), reconnecting in 3s...")
            await asyncio.sleep(3)

asyncio.run(connect())

TypeScript

import WebSocket, { type RawData } from 'ws';

interface WindowOpenEvent {
  event: 'window_open';
  asset: string;
  marketType: string;
  windowStart: number;
  windowStartIso: string;
  price: number;
  source: string;
  snapshot?: boolean;
}

function connect(): void {
  const ws = new WebSocket('wss://api.vatic.trading/ws');

  ws.on('message', (raw: RawData) => {
    const text = typeof raw === 'string' ? raw : raw.toString();
    const msg = JSON.parse(text);

    if (msg.event === 'connected') {
      ws.send(JSON.stringify({
        type: 'subscribe',
        asset: 'btc',
        marketTypes: ['5min', '15min'],
      }));
    }

    if (msg.event === 'window_open') {
      const e = msg as WindowOpenEvent;
      const label = e.snapshot ? 'snapshot' : 'LIVE';
      console.log(`[${label}] ${e.asset} ${e.marketType} — $${e.price} (${e.windowStartIso})`);
    }
  });

  ws.on('close', () => setTimeout(connect, 3000));
  ws.on('error', (err) => console.error('ws error:', err.message));
}

connect();

Event reference

Event	Direction	Description
`connected`	Server → Client	Sent immediately on connect with supported assets and types.
`subscribed`	Server → Client	Confirms a successful subscribe. Followed by current-window snapshots.
`unsubscribed`	Server → Client	Confirms unsubscribe.
`window_open`	Server → Client	Target price pushed at every window boundary. Also sent as snapshot on subscribe.
`window_open_error`	Server → Client	Upstream price fetch failed after all retries.
`hyperliquid_mark_price`	Server → Client	Live Hyperliquid underlying perp mark price, including `oraclePrice`, `midPrice`, `funding`, and `openInterest`.
`error`	Server → Client	Invalid JSON, unknown asset, or unknown message type.
`subscribe`	Client → Server	Subscribe to either Vatic target-price market types or a named real-time channel like `hyperliquid_mark_price`.
`unsubscribe`	Client → Server	Remove all subscriptions for this connection.

Get Started

Real-time

Concepts

Endpoint

Available streams

Why WebSocket over polling?

Market types

Connection flow

1. Connect

Vatic target prices

Hyperliquid mark price

3. Receive price events

4. Unsubscribe

Heartbeat

Examples

Node.js

TypeScript — Hyperliquid mark price

Python

TypeScript

Event reference

​Endpoint

​Available streams

​Why WebSocket over polling?

​Market types

​Connection flow

​1. Connect

​2. Subscribe

​Vatic target prices

​Hyperliquid mark price

​3. Receive price events

​4. Unsubscribe

​Heartbeat

​Examples

​Node.js

​TypeScript — Hyperliquid mark price

​Python

​TypeScript

​Event reference

Endpoint

Available streams

Why WebSocket over polling?

Market types

Connection flow

1. Connect

2. Subscribe

Vatic target prices

Hyperliquid mark price

3. Receive price events

4. Unsubscribe

Heartbeat

Examples

Node.js

TypeScript — Hyperliquid mark price

Python

TypeScript

Event reference