API Quickstart

Quickstart for HyperLink's API: base URLs, request signing, and a working code example to start trading Hyperliquid markets programmatically today.

HyperLink mirrors Hyperliquid's /exchange action format and EIP-712 signing, so point an existing Hyperliquid trading client at the HyperLink base URL.

Quickstart

1. Create an agent wallet, which is your API key, in the web app or with approveAgent. See Authentication & Keys.

2. Store the agent private key in AGENT_PRIVATE_KEY.

3. Install the HyperLink Python SDK and send a signed /exchange request.

Base URL

• HTTP: https://api.hyperlink.xyz

• WebSocket: wss://api.hyperlink.xyz/ws

Endpoints

Method	Path	Purpose
POST	/exchange	Signed trading actions and private read queries.
GET	/ws	WebSocket subscriptions and signed post actions. See WebSocket API.

Request envelope

SDKs build the /exchange envelope for you: action, signature, nonce, plus optional expiresAfter and vaultAddress. There are no bearer tokens or API secrets; authentication is the signature on each request.

For raw request fields, response shapes, and signed read query schemas, see Exchange Methods. EIP-712 signatures use Hyperliquid-compatible signing chainIds, not the HyperEVM network chainId 999; see Authentication & Keys.

First request

Use the HyperLink Python SDK. It is a minimal fork of the Hyperliquid Python SDK with HyperLink defaults and signed private reads. The import paths still use hyperliquid.*.

HyperLink requires a client order ID (cloid) on every order. Pass it through the SDK's cloid parameter or the raw order action's c field.

pip install hyperlink-python-sdk

import os
from eth_account import Account
from hyperliquid.exchange import Exchange
from hyperliquid.utils.types import Cloid

# Your API key is the agent private key. Keep it in an env var, never hardcode.
agent = Account.from_key(os.environ["AGENT_PRIVATE_KEY"])

# The HyperLink SDK defaults to the HyperLink base URL. Set it explicitly if your client code passes a URL.
exchange = Exchange(agent, base_url="https://api.hyperlink.xyz")

# Place a resting limit buy: 0.1 BTC at 50000, good-till-cancel.
result = exchange.order(
    name="BTC",
    is_buy=True,
    sz=0.1,
    limit_px=50000,
    order_type={"limit": {"tif": "Gtc"}},
    cloid=Cloid.from_str("0x1234567890abcdef1234567890abcdef"),  # required
)
print(result)

For TypeScript and longer SDK examples, see SDKs.

Migrate from Hyperliquid

Trading actions need one change: set the base URL to HyperLink. Order structures, asset indexes, and EIP-712 signing stay Hyperliquid-compatible. The HyperLink Python SDK PR shows the minimal changes needed to add HyperLink support to a Hyperliquid SDK fork.

Need	What to do
Trading actions	Use the HyperLink Python SDK, or keep your Hyperliquid client and set the HyperLink base URL.
Private account reads	Send signed POST /exchange queries instead of public /info account-state calls.
Public market data	Keep using Hyperliquid public /info for meta, allMids, l2Book, and candleSnapshot.

The HyperLink Python SDK adds helpers for signed private reads. In other SDKs, build those as raw signed requests, or see SDKs. For every signed read query and schema, see Exchange Methods.

Next steps

• Authentication & Keys: create agent keys and sign requests.

• SDKs: Python and TypeScript client examples.

• Exchange Methods: actions, queries, and schemas.

• WebSocket API: real-time subscriptions.