approveBuilderFee (gRPC) | Hyperliquid API Docs

Approve a maximum fee rate for a builder address on Hyperliquid. Enables DeFi builders to earn fees on routed trades.

Approve a maximum fee rate that a builder (DeFi application) can charge on trades executed on your behalf. Builder codes enable third-party applications to earn fees for order routing.

Sample Data

JSON

{
  "signature": {
    "r": "0x819ad144d5c0c3d55a176f1b61ee61f2ad290f1b4cc2afb3944c2f70235a507d",
    "s": "0x2fea989745633804f70c5528c9258a89b3789bd99c6a03c6a1bd884cf5dc1b6b",
    "v": 28
  },
  "action": {
    "type": "approveBuilderFee",
    "signatureChainId": "0x66eee",
    "hyperliquidChain": "Mainnet",
    "maxFeeRate": "0.01%",
    "builder": "0x6530512a6c89c7cfcebc3ba7fcd9ada5f30827a6",
    "nonce": 1768146914155
  },
  "nonce": 1768146914155
}

View this transaction on Hypurrscan

Field Reference

Action Fields

Field	Type	Description
`type`	string	Always `"approveBuilderFee"`
`maxFeeRate`	string	Maximum fee rate the builder can charge (e.g., `"0.001"` = 0.1%)
`builder`	string	Ethereum address of the builder
`nonce`	number	Timestamp-based nonce for replay protection

Fee Limits

Hyperliquid enforces maximum builder fees:

Market Type	Maximum Builder Fee
Perpetuals	0.1% (10 basis points)
Spot	1% (100 basis points)

Builder codes do not apply to the buying side of spot trades.

How Builder Fees Work

User approves a max fee rate for a builder address
Builder submits orders with a fee parameter: {"b": address, "f": fee_bps}
Fee is deducted from the user's trade and credited to the builder
Builders claim fees through the referral reward system

Use Cases

DeFi Integration Tracking

Monitor which builders users are authorizing:

Python

def process_approveBuilderFee_action(action):
    builder = action.get('builder')
    max_fee = float(action.get('maxFeeRate', 0))

    print(f"Builder approved: {builder} with max fee {max_fee * 100}%")

Fee Analytics

Track builder fee approvals to understand:

Popular trading interfaces
Average fee tolerance
Builder market share

Competition Analysis

Monitor which builders are gaining traction in the Hyperliquid ecosystem.

Requirements

Builder must maintain at least 100 USDC in perps account value
Approval must be signed by the user's main wallet (not an agent)
Users can revoke permissions at any time

approveAgent - Authorize API wallets
order - Orders can include builder fee parameters

approveBuilderFee - Authorize Builder Fees