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PrediX

Quickstart - Python

Buy YES tokens on a PrediX market using web3.py.

Quickstart flow: Setup -> Approve -> Quote -> Trade -> Done. Router handles CLOB -> AMM routing automatically.

Prerequisites

Section titled “Prerequisites”
Terminal window
pip install web3 requests

You need:

  • A wallet private key on Unichain mainnet - gas is sponsored via paymaster for eligible users
  • test-USDC on Unichain (get from Faucet, 10,000 per address)

Complete working example

Section titled “Complete working example”
"""
PrediX - Python Quickstart
Buy YES tokens on a prediction market via Router contract.
"""
import json
import time
from web3 import Web3


# --- Config ---
RPC_URL = "https://mainnet.unichain.org"
PRIVATE_KEY = "0x..."  # your private key
CHAIN_ID = 130  # Unichain mainnet


# Contract addresses (beta)
ROUTER  = "0x39043ba36CF86590668200fb4Be094b9259B917E"
USDC    = "0xB3FCA863dD0F6b496cCDDf6497Da5Dad67857F56"  # beta TestUSDC
PERMIT2 = "0x000000000022D473030F116dDEE9F6B43aC78BA3"


# --- Setup ---
w3 = Web3(Web3.HTTPProvider(RPC_URL))
account = w3.eth.account.from_key(PRIVATE_KEY)
print(f"Wallet: {account.address}")


# --- ABI (minimal) ---
ERC20_ABI = json.loads('[{"name":"approve","type":"function","inputs":[{"name":"spender","type":"address"},{"name":"amount","type":"uint256"}],"outputs":[{"name":"","type":"bool"}]}]')


ROUTER_ABI = json.loads("""[
  {
    "name": "buyYes",
    "type": "function",
    "stateMutability": "nonpayable",
    "inputs": [
      {"name": "marketId", "type": "uint256"},
      {"name": "usdcIn", "type": "uint256"},
      {"name": "minYesOut", "type": "uint256"},
      {"name": "recipient", "type": "address"},
      {"name": "maxFills", "type": "uint256"},
      {"name": "deadline", "type": "uint256"}
    ],
    "outputs": [
      {"name": "yesOut", "type": "uint256"},
      {"name": "clobFilled", "type": "uint256"},
      {"name": "ammFilled", "type": "uint256"}
    ]
  },
  {
    "name": "quoteBuyYes",
    "type": "function",
    "stateMutability": "nonpayable",
    "inputs": [
      {"name": "marketId", "type": "uint256"},
      {"name": "usdcIn", "type": "uint256"},
      {"name": "maxFills", "type": "uint256"}
    ],
    "outputs": [
      {"name": "expectedYesOut", "type": "uint256"},
      {"name": "clobPortion", "type": "uint256"},
      {"name": "ammPortion", "type": "uint256"}
    ]
  }
]""")


usdc = w3.eth.contract(address=USDC, abi=ERC20_ABI)
router = w3.eth.contract(address=ROUTER, abi=ROUTER_ABI)




def approve_usdc():
    """One-time: approve USDC to Permit2."""
    tx = usdc.functions.approve(
        PERMIT2, 10**12  # 1M USDC
    ).build_transaction({
        "from": account.address,
        "nonce": w3.eth.get_transaction_count(account.address),
        "chainId": CHAIN_ID,
    })
    signed = account.sign_transaction(tx)
    tx_hash = w3.eth.send_raw_transaction(signed.raw_transaction)
    receipt = w3.eth.wait_for_transaction_receipt(tx_hash)
    print(f"Approved USDC: {receipt.transactionHash.hex()}")




def quote_buy_yes(market_id: int, usdc_amount: int) -> int:
    """Get expected YES output (non-view - uses eth_call)."""
    result = router.functions.quoteBuyYes(
        market_id, usdc_amount, 10
    ).call({"from": account.address})
    expected_out, clob, amm = result
    print(f"Quote: {expected_out} YES (CLOB: {clob}, AMM: {amm})")
    return expected_out




def buy_yes(market_id: int, usdc_amount: int, min_out: int):
    """Execute buyYes trade."""
    deadline = int(time.time()) + 300  # 5 min
    tx = router.functions.buyYes(
        market_id,
        usdc_amount,
        min_out,
        account.address,
        10,  # maxFills
        deadline,
    ).build_transaction({
        "from": account.address,
        "nonce": w3.eth.get_transaction_count(account.address),
        "chainId": CHAIN_ID,
    })
    signed = account.sign_transaction(tx)
    tx_hash = w3.eth.send_raw_transaction(signed.raw_transaction)
    receipt = w3.eth.wait_for_transaction_receipt(tx_hash)
    print(f"Trade complete: {receipt.transactionHash.hex()}")
    return receipt




if __name__ == "__main__":
    # Step 1: Approve (run once)
    # approve_usdc()


    # Step 2: Quote
    market_id = 1
    usdc_in = 100 * 10**6  # 100 USDC (6 decimals)
    expected = quote_buy_yes(market_id, usdc_in)


    # Step 3: Execute with 0.5% slippage
    min_out = expected * 995 // 1000
    buy_yes(market_id, usdc_in, min_out)

Run

Section titled “Run”
Terminal window
export PRIVATE_KEY="0x..."
python quickstart.py

Key notes

Section titled “Key notes”
  • Price precision: 1e6 = 100%. Prices range $0.01-$0.99.
  • USDC: 6 decimals. 100 * 10**6 = 100 USDC.
  • Quote functions are NOT view - they must be called via eth_call (.call() in web3.py). They return (0, 0, 0) on invalid market state, never revert.
  • marketId is uint256 (not bytes32).
  • maxFills: how many CLOB orders to try matching. 10 is a good default.
  • Routing: Router tries CLOB first, then AMM (Uniswap v4) for remainder. Unused input refunded automatically.

Exchange functions (CLOB direct)

Section titled “Exchange functions (CLOB direct)”

For advanced users who want to interact with the CLOB directly:

# Place limit order
# placeOrder(marketId, side, price, amount, builder)
# side: 0=BUY_YES, 1=SELL_YES, 2=BUY_NO, 3=SELL_NO
# price: 1e6 = 100%, e.g. 450000 = $0.45


# Cancel order
# cancelOrder(orderId)  - orderId is bytes32


# View orderbook
# getOrderBook(marketId, depth) -> yesBids, yesAsks, noBids, noAsks
# getBestPrices(marketId) -> bestBidYes, bestAskYes, bestBidNo, bestAskNo

See Router integration for detailed Exchange API.

Next steps

Section titled “Next steps”