> ## Documentation Index
> Fetch the complete documentation index at: https://docs.struct.to/llms.txt
> Use this file to discover all available pages before exploring further.

# Asset Prices

> Stream real-time crypto asset price ticks.

<Note>
  **Room ID:** `polymarket_asset_prices` \
  **Endpoint:** `wss://api.struct.to/ws` \
  **Rate:** 0.005 credits per message
</Note>

Stream real-time crypto asset price ticks. Leave `asset_symbols` empty to subscribe to all available assets.

<Tip>
  **Related guide:** [Crypto Up/Down feed](/guides/crypto-up-down-feed) uses this room for live spot ticks behind Up/Down markets.
</Tip>

## Subscribe

All filters are optional. If `asset_symbols` is omitted or empty, the room subscribes to price ticks for every tracked asset.

### Filters

| Filter          | Type       | Required | Description                                   |
| --------------- | ---------- | -------- | --------------------------------------------- |
| `asset_symbols` | `string[]` | No       | Asset symbols to track, e.g. `["BTC", "ETH"]` |

### Example

```json theme={null}
{
  "type": "join_room",
  "payload": {
    "room_id": "polymarket_asset_prices"
  }
}
```

```json theme={null}
{
  "type": "room_message",
  "payload": {
    "room_id": "polymarket_asset_prices",
    "message": {
      "action": "subscribe",
      "asset_symbols": ["BTC", "ETH"]
    }
  }
}
```

### Response

```json theme={null}
{
  "type": "asset_prices_stream_subscribe_response",
  "room_id": "polymarket_asset_prices",
  "data": {
    "asset_symbols": ["BTC", "ETH"]
  }
}
```

## Events

### `asset_price_tick`

```json theme={null}
{
  "type": "asset_price_tick",
  "room_id": "polymarket_asset_prices",
  "data": {
    "event_type": "tick",
    "symbol": "BTC",
    "price": 97250.50,
    "timestamp_ms": 1743500000000,
    "published_at": 1743500000000
  }
}
```

### `asset_price_window_update`

```json theme={null}
{
  "type": "asset_price_window_update",
  "room_id": "polymarket_asset_prices",
  "data": {
    "event_type": "window_update",
    "symbol": "ETH",
    "variant": "1h",
    "start_time": 1743496400000,
    "end_time": 1743500000000,
    "open_price": 3200.0,
    "close_price": 3215.50,
    "update_type": "close",
    "published_at": 1743500000000
  }
}
```