WebSocket Reference

Base URL:

wss://markets.hit.com

For /user API key signatures, see Developer Authentication.

Namespaces

`/`

Authentication: Public Public order book and event data.

`/user`

Authentication: API key HMAC User-specific balances, positions, orders, and trades.

Public Client Messages

Event	Payload type	Description
`ping`	`PingPayload`	Health check.
`orderbook-market-connect`	`OrderbookTokenIds`	Subscribe to outcome token IDs.
`orderbook-market-disconnect`	`OrderbookTokenIds`	Unsubscribe from outcome token IDs.
`event-connect`	UUID string or omitted	Subscribe to an event UUID, or all event updates when omitted.
`event-disconnect`	UUID string or omitted	Unsubscribe from an event UUID, or the all-events subscription when omitted.

PingPayload:

Field	Type	Required	Description
none	object	No	Send an empty object.

orderbook-market-connect

Authentication: Public Subscribe to one or more outcome token IDs. Use the market tokenId1 and tokenId2 values from market data when you want both sides of a binary market. Payload type: OrderbookTokenIds.

[
  "66539633449217268141320411658481757807854020589069449399851604049177251401512"
]

Socket.IO example:

socket.emit("orderbook-market-connect", [
  "66539633449217268141320411658481757807854020589069449399851604049177251401512",
]);

On subscribe, the backend joins one order book room per token ID and requests an initial snapshot for each token. Successful snapshots are emitted on orderbook as an OrderBook[]. Live level changes are emitted later on orderbook-price-change. If an initial snapshot cannot be loaded because of a transient backend failure, the server emits orderbook-error with the affected tokenIds. Unknown token IDs may produce no snapshot and no error.

Unsubscribe from Token Order Books

orderbook-market-disconnect

Authentication: Public Stop receiving order book snapshots and deltas for one or more outcome token IDs. Payload type: OrderbookTokenIds.

[
  "66539633449217268141320411658481757807854020589069449399851604049177251401512"
]

Socket.IO example:

socket.emit("orderbook-market-disconnect", [
  "66539633449217268141320411658481757807854020589069449399851604049177251401512",
]);

The backend does not emit a dedicated unsubscribe confirmation event. OrderbookTokenIds:

Field	Type	Required	Description
none	string[]	Yes	Array of outcome token IDs.

Public Server Events

Event	Payload type	Description
`pong`	`PongPayload`	Ping response.
`app-error`	`AppError`	WebSocket error frame.
`orderbook`	`OrderBook[]`	Order book snapshot.
`orderbook-price-change`	`OrderBookPriceChange`	Price level delta.
`orderbook-error`	`OrderBookError`	Transient snapshot load failure.
`event-onchain-update`	`EventOnchainUpdatePublic` or `EventOnchainUpdateRaw`	On-chain event or market update.
`tick-size-change`	`TickSizeChange`	Market tick size update.
`order-speed-bump-pending`	`OrderSpeedBumpPending`	Order delayed before matching.

PongPayload:

Field	Type	Required	Description
none	object	No	Empty object.

AppError:

Field	Type	Required	Description
`message`	string or object	Yes	Error message or structured WebSocket exception payload.

OrderBook:

Field	Type	Required	Description
`market`	UUID string	Yes	Market UUID.
`asset_id`	string	Yes	Outcome token ID.
`hash`	string	Yes	Book state hash.
`timestamp`	integer	Yes	Book timestamp.
`bids`	`OrderBookLevel[]`	Yes	Bid price levels.
`asks`	`OrderBookLevel[]`	Yes	Ask price levels.
`tick_size`	string	Yes	Minimum price increment.

OrderBookLevel:

Field	Type	Required	Description
`price`	string	Yes	Price level.
`size`	string	Yes	Available size at the level.

OrderBookPriceChange:

Field	Type	Required	Description
`asset_id`	string	Yes	Outcome token ID.
`market`	UUID string	Yes	Market UUID.
`changes`	`OrderBookPriceLevel[]`	Yes	Changed price levels.
`timestamp`	string	Yes	Delta timestamp.
`hash`	string	Yes	Book state hash after the delta.
`tick_size`	string	Yes	Minimum price increment.

OrderBookPriceLevel:

Field	Type	Required	Description
`price`	string	Yes	Price level.
`side`	enum string	Yes	`buy` or `sell`.
`size`	string	Yes	New size at the level.

OrderBookError:

Field	Type	Required	Description
`tokenIds`	string[]	Yes	Token IDs whose initial snapshot could not be loaded.
`reason`	enum string	Yes	`snapshot_unavailable`.
`retryable`	boolean	Yes	Whether the client should retry.

EventOnchainUpdatePublic:

Field	Type	Required	Description
`event_type`	enum string	Yes	`event_onchain_update`.
`eventId`	UUID string	Yes	Event UUID.
`marketId`	UUID string	Yes	Market UUID.
`status`	enum string	Yes	`proposed` or `resolved`.
`timestamp`	integer	No	Block timestamp.

EventOnchainUpdateRaw:

Field	Type	Required	Description
`eventId`	UUID string	Yes	Event UUID.
`marketId`	UUID string	Yes	Market UUID.
`ancillaryData`	string	Yes	UMA ancillary data.
`status`	enum string	Yes	`initialized`, `registered`, `proposed`, `resolved`, `disputed`, `settled`, or `paused`.
`from`	boolean	Yes	Previous on-chain boolean state.
`to`	boolean	Yes	New on-chain boolean state.
`blockTimestamp`	integer	No	Block timestamp.

TickSizeChange:

Field	Type	Required	Description
`event_type`	enum string	Yes	`tick_size_change`.
`market`	UUID string	Yes	Market UUID.
`old_tick_size`	string	Yes	Previous tick size.
`new_tick_size`	string	Yes	New tick size.
`timestamp`	integer	Yes	Event timestamp.

OrderSpeedBumpPending:

Field	Type	Required	Description
`market`	UUID string	Yes	Market UUID used as the subscription key.
`orderId`	UUID string	No	Delayed order UUID when supplied by the producer.
additional fields	object	No	The backend forwards any additional producer fields unchanged.

User Client Messages

Event	Payload type	Description
`user-connect`	`UserConnectPayload`	Authenticate and subscribe to the user channel.
`user-disconnect`	empty object	Unsubscribe from the user channel.
`initial-data`	empty object	Request initial collateral balances.
`initial-shares-by-market`	UUID string	Request shares for a market and subscribe to share updates.
`shares-by-market-disconnect`	empty object	Stop share update subscriptions for the user proxy wallet.

UserConnectPayload:

Field	Type	Required	Description
`auth`	`TradingApiKeyAuth`	Yes	API key WebSocket auth payload.

TradingApiKeyAuth:

Field	Type	Required	Description
`apiKey`	string	Yes	API key identifier.
`signature`	string	Yes	HMAC-SHA256 signature.
`timestamp`	string	Yes	Unix timestamp in milliseconds.
`passphrase`	string	Yes	API passphrase.

User Server Events

Event	Payload type	Description
`user-authenticated`	`UserAuthenticated`	Authentication result.
`app-error`	`AppError`	WebSocket error frame.
`collateral-balance`	`BalanceUpdate`	Proxy wallet collateral balance.
`collateral-balance-eoa`	`BalanceUpdate`	EOA collateral balance.
`shares-by-market-update`	`MarketSharesUpdate`	Shares update for a subscribed market.
`user-positions-update`	`UserPositionUpdate`	Position update.
`user-order`	`UserOrderEvent[]`	Order update.
`user-trade`	`TradeEvent[]`	Trade update.
`user-mp-update`	`UserMpUpdate`	Rewards accrual update.
`user-mp-claim-update`	`UserMpClaimUpdate`	Rewards claim dispatch update.
`transaction`	`TransactionUpdate`	Transaction status update.

UserAuthenticated:

Field	Type	Required	Description
`success`	boolean	Yes	Whether authentication succeeded.
`error`	string	No	Failure reason.

BalanceUpdate:

Field	Type	Required	Description
`value`	string	Yes	Token balance.

MarketSharesUpdate:

Field	Type	Required	Description
`marketId`	UUID string	Yes	Market UUID.
`user`	`SocketUser`	Yes	Authenticated user object.
`token1`	`MarketShareToken`	Yes	Outcome 1 token balance.
`token2`	`MarketShareToken`	Yes	Outcome 2 token balance.

MarketShareToken:

Field	Type	Required	Description
`id`	string	Yes	Outcome token ID.
`balance`	string	Yes	Token balance.

SocketUser:

Field	Type	Required	Description
`id`	UUID string	Yes	Hit user ID.
`evmAddress`	address string	Yes	User EOA address.
`email`	string	No	User email when available.
`proxyWalletAddress`	address string	No	User proxy wallet address.
`proxyWalletSetup`	boolean	Yes	Whether proxy wallet setup is complete.
`createdAt`	string (date-time)	Yes	User creation timestamp.
`updatedAt`	string (date-time)	Yes	Last user update timestamp.
`nonce`	string	Yes	User auth nonce.
`name`	string	Yes	Display name.
`imageURL`	string	Yes	Profile image URL.
`roles`	object[]	No	User roles.

UserPositionUpdate:

Field	Type	Required	Description
`tokenId`	string	Yes	Outcome token ID.
`proxyAddress`	address string	Yes	User proxy wallet address.
`amount`	string	Yes	Updated token amount.
`acquisitionPrice`	number	Yes	Acquisition price.
`timestamp`	string (date-time)	Yes	Update timestamp.

UserOrderEvent:

Field	Type	Required	Description
`event_type`	enum string	Yes	`order`.
`asset_id`	string	Yes	Outcome token ID.
`associate_trades`	string[] or null	Yes	Associated trade IDs. Currently `null`.
`id`	UUID string	Yes	Order UUID.
`market`	UUID string	Yes	Market UUID.
`order_owner`	UUID string	Yes	Order owner user ID.
`original_size`	string	Yes	Submitted order size.
`outcome`	string	Yes	Outcome label.
`owner`	UUID string	Yes	Order owner user ID.
`price`	string	Yes	Order price.
`side`	enum string	Yes	`buy` or `sell`.
`size_matched`	string	Yes	Matched size.
`timestamp`	string	Yes	Order creation timestamp converted to Unix milliseconds string.
`type`	enum string	Yes	`PLACEMENT`, `UPDATE`, `CANCELLATION`, or `REJECTION`.
`rejection_reason`	string	No	Present when `type=REJECTION`. Known values include `no_fill_available`, `insufficient_balance`, `stale_nonce`, and `onchain_revert:{reason}`.

TradeEvent:

Field	Type	Required	Description
`event_type`	enum string	Yes	`trade`.
`asset_id`	string	Yes	Outcome token ID.
`id`	UUID string	Yes	Trade UUID.
`last_update`	string	Yes	Last update timestamp converted to Unix milliseconds string.
`maker_orders`	`TradeMakerOrder[]`	Yes	Maker orders that filled the trade.
`market`	UUID string	Yes	Market UUID.
`match_time`	string	Yes	Match timestamp converted to Unix milliseconds string.
`outcome`	string	Yes	Outcome label.
`owner`	UUID string	Yes	User ID receiving this event.
`price`	string	Yes	Fill price.
`side`	enum string	Yes	`buy` or `sell`.
`trader_side`	enum string	Yes	`MAKER` or `TAKER`.
`size`	string	Yes	Filled size.
`status`	enum string	Yes	`MATCHED`, `MINED`, `CONFIRMED`, or `FAILED`.
`taker_order_id`	UUID string	Yes	Taker order UUID.
`timestamp`	string	Yes	Emit timestamp converted to Unix milliseconds string.
`trade_owner`	UUID string	Yes	Taker owner user ID.
`type`	enum string	Yes	`TRADE`.

TradeMakerOrder:

Field	Type	Required	Description
`asset_id`	string	Yes	Outcome token ID.
`matched_amount`	string	Yes	Amount matched from this maker order.
`order_id`	UUID string	Yes	Maker order UUID.
`outcome`	string	Yes	Outcome label.
`owner`	UUID string	Yes	Maker owner user ID.
`price`	string	Yes	Maker fill price.

UserMpUpdate:

Field	Type	Required	Description
`userId`	UUID string	Yes	Hit user ID.
`marketId`	UUID string	Yes	Market UUID.
`mpDelta`	string	Yes	MP accrued in the epoch.
`epochDate`	string	Yes	Reward epoch date.
`projectedDailyUsdc`	string	No	Projected daily USDC value.

UserMpClaimUpdate:

Field	Type	Required	Description
`userId`	UUID string	Yes	Hit user ID.
`recipientAddress`	address string	No	Claim recipient address.
`claimableMicroUsdc`	string	No	Claimable amount in micro-USDC.
`rowCount`	integer	No	Number of settlement rows included.
`outcome`	enum string	No	`dispatched` or `error`. Missing values should be treated as `dispatched`.
`reason`	string	No	Failure reason, such as `signer-missing`, `executor-failed`, or `task-error`.

TransactionUpdate:

Field	Type	Required	Description
`event_type`	enum string	Yes	`transaction`.
`txHash`	string	Yes	Transaction hash.
`status`	enum string	Yes	`success` or `failed`.
`operationType`	enum string	No	`proxy_wallet_create`, `proxy_wallet_setup`, `redeem_position`, or `multisend`.
`timestamp`	integer	Yes	Emit timestamp in milliseconds.

Overview

Market Data

Trading

Realtime

Namespaces

`/`

`/user`

Public Client Messages

Unsubscribe from Token Order Books

Public Server Events

User Client Messages

User Server Events

Overview

Market Data

Trading

Realtime

Documentation Index

​Namespaces

​/

​/user

​Public Client Messages

​Subscribe to Token Order Books

​Unsubscribe from Token Order Books

​Public Server Events

​User Client Messages

​User Server Events

Namespaces

`/`

`/user`

Public Client Messages

Subscribe to Token Order Books

Unsubscribe from Token Order Books

Public Server Events

User Client Messages

User Server Events