Order Updates

HyperliquidPolymarket

Sends an initial snapshot, including orders: [] when there are no relevant orders, then subsequent updates with isSnapshot: false. Terminal Polymarket orders can remain in the snapshot while matched fills await settlement.

{
  "method": "subscribe",
  "subscription": {
    "type": "orderUpdates",
    "user": "0x1111111111111111111111111111111111111111"
  }
}

Response

{
  "channel": "orderUpdates",
  "data": {
    "isSnapshot": true,
    "user": "0x1111111111111111111111111111111111111111",
    "orders": [
      {
        "order": {
          "coin": "BTC",
          "marketAssetId": "00020000",
          "side": "B",
          "limitPx": "50000.00",
          "sz": "0.1",
          "oid": "0x1234567890abcdef...",
          "timestamp": 1701234567890,
          "origSz": "0.1",
          "orderType": "stop_limit",
          "tif": "Gtc",
          "isPositionTpsl": false,
          "isTrigger": true,
          "triggerCondition": "tp",
          "triggerPx": "50500.00",
          "reduceOnly": false,
          "parentOrderId": null
        },
        "status": "waitingForTrigger",
        "statusTimestamp": 1701234567890
      }
    ]
  }
}

Confirmed order replacements

A confirmed modify can include modification alongside order and status on the replacement order’s update:

Field	Type	Description
`previousOrderId`	string	Notional order ID replaced by `order.oid`
`previousTotalSz`	string	Original total size of the replaced order
`reason`	string	Optional `user_request`, `position_size_changed`, or `reduce_only_exceeds_position`

This metadata is absent on an unconfirmed modifying request and when the old order cannot be read. A canceled update with cancelReason: "modified" removes the old order; the replacement’s update confirms its outcome. Do not treat a modify request alone as a successful size reduction.

Prediction-market outcomes

Both Hyperliquid and Polymarket outcomes use this channel:

Hyperliquid-routed outcomes use a 16-character HL_Outcome marketAssetId.
Polymarket-routed outcomes use a 68-character PM_Outcome marketAssetId; coin can be a fallback label such as PM_Outcome:12345678901234567890.

Use the Notional oid for cancel requests and matching later updates. Fok is preserved as tif: "Fok"; Gtd and Fak may currently appear as tif: null. Polymarket updates backed by canonical fill-settlement facts include order.filledSz, the exact CLOB-matched share quantity. Use it for executed size instead of deriving origSz - sz: valid buy price improvement can execute more shares than origSz without exceeding the signed quote budget. Use polymarketFills on the order-update object for matched, failed, and finalized settlement transitions. After Polygon finality, Polymarket also publishes the finalized trade through userFills; re-read polymarketPositions and assets for canonical shares and pUSD balances. After a Hyperliquid outcome fill, use userFills and outcomeBalances.

polymarketFills[]

This optional array is on each update alongside order, status, and statusTimestamp:

Field	Type	Description
`venueTradeId`	string	Venue trade identifier for correlation
`settlementStatus`	string	`"matched"`, `"failed"`, or `"finalized"`
`size`	string	Matched outcome-share quantity
`price`	string	Match price

matched is provisional. Outcome shares are not credited until settlement finalizes. A later failed transition does not represent an executed fill; refresh canonical balances after a finalized transition.

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Response

Confirmed order replacements

Prediction-market outcomes

polymarketFills[]

​Subscribe

​Response

​Confirmed order replacements

​Prediction-market outcomes

​polymarketFills[]

Subscribe

Response

Confirmed order replacements

Prediction-market outcomes

polymarketFills[]