Predict and Hyperliquid market identifiers

Start with an active Predict outcome. The catalog returns hl_id, hl_long_asset_id, hl_short_asset_id, long_label, short_label, and, when applicable, hl_question_id.

For hl_id = N and side S:

encoding                = 10 * N + S
market-data coin        = #<encoding>
balance token           = +<encoding>
exchange order asset ID = 100000000 + encoding

Only side 0 and side 1 are valid. Side 0 uses long_label; side 1 uses short_label.

Example

For hl_id = 14484:

Prefer the catalog’s hl_long_asset_id and hl_short_asset_id for signed order actions. Derive the values when reading /info or opening a WebSocket subscription.

Side is not direction

Selecting side 0 or side 1 chooses the token. The order’s b field separately chooses whether to buy (true) or sell (false) that token.

Because HIP-4 uses complementary books, buying side 0 at p is economically equivalent to selling side 1 at 1 - p. Hyperliquid merges that liquidity. Do not fetch both side books and add their levels together.

hl_question_id identifies a mutually exclusive question for mergeQuestion and negateOutcome. It is not an order-routing asset ID.

Precision

HIP-4 outcome sizes use whole-share increments (szDecimals = 0). Prices follow Hyperliquid’s spot-style precision rules and may contain at most five significant figures. Orders must meet Hyperliquid’s minimum notional, currently 10 quote tokens. Strip insignificant trailing zeroes before signing.