Perps API Overview

The Perps API is the same backend the HyperFlow app trades through. It gives you programmatic access to markets, order placement, account state, and transfers.

Base URL: https://perps-api.hyperflow.fun/api/v1 — mainnet only. No invite or allowlisting is required; any wallet can register a trading key and trade.

Integration at a glance

The pages in this section

Response envelope

Every endpoint wraps its payload in the same envelope:

{ "success": true, "data": { "...": "..." }, "timestamp": 1787067314951 }

Errors return success: false with an error object:

{ "success": false, "error": { "code": "...", "message": "..." }, "timestamp": 1787067314951 }

Batch and asynchronous routes return 200 with the outcome per item in data (status, reason); cancel-batch can return 200 with success: false. Read the items, not the envelope.

• timestamp is Unix milliseconds.
• Prices, sizes, and amounts are decimal strings ("0.00159", "2000") — never floats. (Non-monetary ratios like /config’s trader_share are plain JSON numbers.)

Account format

Endpoints identify you by one of two values, and each endpoint’s reference states which one it takes:

Derive the account id by right-padding the wallet with a subaccount tail. Index 0 is your default account, so in practice the account id is the lowercase wallet followed by 24 hex zeros:

account_id = <wallet address> || <11 zero bytes> || <1-byte subaccount index>

const accountId = (wallet.toLowerCase() + "00".repeat(11) + "00") as `0x${string}`;

Authentication model

There is no transport-level auth — no API keys, no bearer tokens. Instead:

• Reads need no signature. They are keyed by wallet or account id, so you can query your own state without holding a key. Treat your account data as readable, not private.
• Writes are signed. Every state-changing request carries an EIP-712 signature in the body plus a single-use millisecond nonce, and the server recovers the signer from it — see Authentication & Signing.

Market data

HyperFlow does not proxy market data — read it from Hyperliquid’s public API, which is the venue of execution:

Hyperliquid endpoints: https://api.hyperliquid.xyz (REST) and wss://api.hyperliquid.xyz/ws (WebSocket) — see the Hyperliquid API docs.

Join on hl_symbol or hl_asset_index, not symbol. The HyperFlow API does not serve mark prices. Hyperliquid funding is hourly.

GET /markets

Static per-market configuration. Live response (trimmed):

{
  "data": [{
    "symbol": "BTC",
    "hl_symbol": "BTC",
    "hl_asset_index": 0,
    "max_leverage": 20,
    "display_max_leverage": 20,
    "initial_margin_ratio": "0.025",
    "maintenance_margin_ratio": "0.015",
    "maker_fee_rate": "0.00015",
    "taker_fee_rate": "0.00045",
    "min_order_value": "10",
    "max_notional": "0",
    "max_open_orders": 20,
    "slippage_bps": 50,
    "tick_size": "1",
    "sz_decimals": 5,
    "px_decimals": 1,
    "only_isolated": false,
    "is_active": true
  }],
  "success": true,
  "timestamp": 1787067314951
}

• max_notional: "0" is the no-ceiling sentinel — treat it as “no maximum order value”, never as a zero cap.
• slippage_bps is the default slippage bound the app applies to market orders; you are free to compute your own.
• sz_decimals / px_decimals bound how many decimals a size and a price may carry; tick_size is the price increment and binds harder than px_decimals — see Price and size rules.

Practical limits

Fixed by the API:

Set per market, and returned by GET /markets — read them at runtime rather than hardcoding, because they change:

Not published: rate limits, the withdrawal ceilings behind ABOVE_MAX / DAILY_LIMIT_EXCEEDED, and a changelog — schema changes are announced on Discord.

Next: Authentication & Signing