ccxt

The change

ccxt builds every Hyperliquid URL from urls['api']['public'] and urls['api']['private'] (hyperliquid.sign()). Anything you pass to the constructor is deep-merged over ccxt’s defaults (Exchange.__init__: settings = self.deep_extend(self.describe(), config)). So the URL override goes into the constructor.

exchange = ccxt.hyperliquid({
    "walletAddress": "0xYourAccountAddress",
    "privateKey": "0x…API wallet key…",
    "privateKey": "0x…client key from Guard…",
    "urls": {"api":  {"public": "http://127.0.0.1:8547", "private": "http://127.0.0.1:8547"},
             "test": {"public": "http://127.0.0.1:8547", "private": "http://127.0.0.1:8547"}},
    "options": {"builderFee": False, "refSet": True},
})

Full example (Python)

import ccxt

GUARD = "http://127.0.0.1:8547"

exchange = ccxt.hyperliquid({
    "walletAddress": "0xYourAccountAddress",  # your main account, not the API wallet
    "privateKey": "0x...",                    # the client key Guard printed
    "urls": {
        "api":  {"public": GUARD, "private": GUARD},
        "test": {"public": GUARD, "private": GUARD},
    },
    "options": {"builderFee": False, "refSet": True},
})

# The entry and its stop in one request (Hyperliquid grouping "normalTpsl").
order = exchange.create_order(
    "BTC/USDC:USDC", "limit", "buy", 0.5, 60000,
    params={"stopLoss": {"triggerPrice": 58800, "type": "market"}},
)

The stopLoss parameter makes ccxt send the entry and a reduce-only stop together, with grouping normalTpsl (create_orders_request()). Guard sizes the entry from that stop. Without a stop the entry is refused under the default rules (why).

JavaScript takes the same keys: new ccxt.hyperliquid({ walletAddress, privateKey, urls, options }).

The config keys

Key	Value	Why
`walletAddress`	your Hyperliquid account address	ccxt requires it (`requiredCredentials`); Guard checks it is the account it guards
`privateKey`	the Guard client key	Hyperliquid does not accept it; only your Guard does
`urls.api.public`, `urls.api.private`	Guard’s URL	every request goes to Guard
`urls.test.public`, `urls.test.private`	Guard’s URL	ccxt’s `set_sandbox_mode(True)` replaces `urls['api']` with `urls['test']`. Without this override, turning on sandbox mode would send orders straight to Hyperliquid testnet, around Guard
`options.builderFee`	`False`	see below
`options.refSet`	`True`	see below

Two ccxt defaults behind Guard

On its first private call ccxt runs initialize_client(), which does two things you do not want behind Guard:

handle_builder_fee_approval() approves ccxt’s own builder address (0x6530…27a6) at feeRate (default 0.01%). With builderFee: False it still approves, at 0%. The approval is a user-signed action, which Guard refuses (only your main wallet can approve a builder fee). ccxt catches the error and sets builderFee to False; approvedBuilderFee stays False, so ccxt attaches no builder to orders.
set_ref() sends setReferrer with code CCXT1. Guard refuses it as a non-trading action. ccxt ignores the error. refSet: True skips the request.

Both refusals are harmless; the options only save two refused requests at start-up.

What to expect

An oversized order comes back filled at a smaller size. Read the filled amount; do not assume the size you sent.
A refused order raises a ccxt ExchangeError whose message carries Guard’s reason and veto code.
fetch_balance, fetch_positions and market data pass through to Hyperliquid unchanged.

Sources

ccxt, python/ccxt/hyperliquid.py: describe() (urls, requiredCredentials, options), sign(), initialize_client(), handle_builder_fee_approval(), set_ref(), create_orders_request().
ccxt, python/ccxt/base/exchange.py: Exchange.__init__, set_sandbox_mode().
ccxt manual, Hyperliquid.