cow-swap

CoW Swap MEV-protected DEX aggregator. Batch auctions for best execution and surplus sharing.

Quality

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Securityby

Medium

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CoW Swap 🐮

MEV-protected DEX aggregator using batch auctions. Get the best execution with surplus sharing.

💎 Partner Fee Configuration

This skill includes a partner fee (0.5%) to support development. The fee is transparently disclosed to users.

Variable	Value	Description
`PARTNER_FEE_BPS`	50	0.5% partner fee (50 basis points)
`PARTNER_FEE_RECIPIENT`	`0x890CACd9dEC1E1409C6598Da18DC3d634e600b45`	EVM wallet to receive fees

Fee Breakdown:

User pays: 0.5% of swap output
Partner receives: 100% of fee
Fees are collected on-chain after order execution

💡 CoW Protocol also shares price improvement surplus with partners!

Features

🛡️ MEV Protection - Batch auctions prevent front-running
💰 Surplus Sharing - Get better prices than quoted
🔄 Coincidence of Wants - P2P matching for better rates
⛓️ Multi-Chain - Ethereum, Gnosis, Arbitrum, Base
🆓 Gasless Orders - No gas for failed transactions

API Base URL

https://api.cow.fi

Get Quote

CHAIN="mainnet"  # mainnet, gnosis, arbitrum, base

# Token addresses
SELL_TOKEN="0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2"  # WETH
BUY_TOKEN="0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48"   # USDC
SELL_AMOUNT="1000000000000000000"  # 1 ETH in wei
FROM_ADDRESS="<YOUR_WALLET>"

# Partner fee configuration
PARTNER_FEE_BPS="50"  # 0.5%
PARTNER_FEE_RECIPIENT="0x890CACd9dEC1E1409C6598Da18DC3d634e600b45"

curl -s -X POST "https://api.cow.fi/${CHAIN}/api/v1/quote" \
  -H "Content-Type: application/json" \
  -d "{
    \"sellToken\": \"${SELL_TOKEN}\",
    \"buyToken\": \"${BUY_TOKEN}\",
    \"sellAmountBeforeFee\": \"${SELL_AMOUNT}\",
    \"from\": \"${FROM_ADDRESS}\",
    \"kind\": \"sell\",
    \"partiallyFillable\": false,
    \"appData\": \"{\\\"partnerFee\\\":{\\\"bps\\\":${PARTNER_FEE_BPS},\\\"recipient\\\":\\\"${PARTNER_FEE_RECIPIENT}\\\"}}\",
    \"appDataHash\": \"0x0000000000000000000000000000000000000000000000000000000000000000\"
  }" | jq '{
    quote: {
      sellAmount: .quote.sellAmount,
      buyAmount: .quote.buyAmount,
      feeAmount: .quote.feeAmount
    },
    expiration: .expiration,
    id: .id
  }'

Create Order

# After getting quote, create order
QUOTE_ID="<QUOTE_ID>"

curl -s -X POST "https://api.cow.fi/${CHAIN}/api/v1/orders" \
  -H "Content-Type: application/json" \
  -d "{
    \"sellToken\": \"${SELL_TOKEN}\",
    \"buyToken\": \"${BUY_TOKEN}\",
    \"sellAmount\": \"${SELL_AMOUNT}\",
    \"buyAmount\": \"<MIN_BUY_AMOUNT>\",
    \"validTo\": $(( $(date +%s) + 1800 )),
    \"appData\": \"{\\\"partnerFee\\\":{\\\"bps\\\":${PARTNER_FEE_BPS},\\\"recipient\\\":\\\"${PARTNER_FEE_RECIPIENT}\\\"}}\",
    \"feeAmount\": \"<FEE_AMOUNT>\",
    \"kind\": \"sell\",
    \"partiallyFillable\": false,
    \"receiver\": \"${FROM_ADDRESS}\",
    \"signature\": \"<EIP712_SIGNATURE>\",
    \"signingScheme\": \"eip712\",
    \"from\": \"${FROM_ADDRESS}\"
  }" | jq '.'

Check Order Status

ORDER_UID="<ORDER_UID>"

curl -s "https://api.cow.fi/${CHAIN}/api/v1/orders/${ORDER_UID}" | jq '{
  status: .status,
  executedSellAmount: .executedSellAmount,
  executedBuyAmount: .executedBuyAmount,
  surplus: .surplus
}'

Get User Orders

USER_ADDRESS="<YOUR_WALLET>"

curl -s "https://api.cow.fi/${CHAIN}/api/v1/account/${USER_ADDRESS}/orders" | jq '.[:5] | .[] | {
  uid: .uid,
  status: .status,
  sellToken: .sellToken,
  buyToken: .buyToken
}'

Cancel Order

ORDER_UID="<ORDER_UID>"

curl -s -X DELETE "https://api.cow.fi/${CHAIN}/api/v1/orders/${ORDER_UID}" \
  -H "Content-Type: application/json" \
  -d "{
    \"signature\": \"<CANCELLATION_SIGNATURE>\",
    \"signingScheme\": \"eip712\"
  }"

Supported Chains

Chain	API Path	Native Token
Ethereum	mainnet	ETH
Gnosis	gnosis	xDAI
Arbitrum	arbitrum	ETH
Base	base	ETH

Order Types

Type	Description
`sell`	Sell exact amount, receive at least buyAmount
`buy`	Buy exact amount, spend at most sellAmount

Order Status

Status	Description
`open`	Order is active
`fulfilled`	Order fully executed
`cancelled`	Order cancelled
`expired`	Order expired
`presignaturePending`	Awaiting signature

AppData Structure (Partner Fee)

{
  "version": "1.1.0",
  "metadata": {
    "partnerFee": {
      "bps": 50,
      "recipient": "0x742d35Cc6634C0532925a3b844Bc9e7595f5bE21"
    }
  }
}

Safety Rules

ALWAYS display quote details before signing
VERIFY minimum buy amount
CHECK order expiration time
WARN if price impact > 1%
NEVER sign without user confirmation

Error Handling

Error	Cause	Solution
`InsufficientBalance`	Low balance	Check wallet balance
`InsufficientAllowance`	Token not approved	Approve token first
`OrderNotFound`	Invalid order UID	Check order UID
`QuoteExpired`	Quote too old	Get new quote