Order Book

Order book operations allow you to retrieve the current state of the order book for specific markets, including bid and ask orders.

Methods

Get Order Book

Retrieve the order book for a specific token:

const orderBook = await client.book.getOrderBook({
  tokenId: "your-token-id"
});

Parameters:

• tokenId (string): The token ID for the market outcome

Returns: OrderBook

OrderBook Type

interface OrderBook {
  bids: OrderBookEntry[];  // Buy orders, sorted by price (highest first)
  asks: OrderBookEntry[];  // Sell orders, sorted by price (lowest first)
  timestamp: number;
}

interface OrderBookEntry {
  price: string;    // Price per share
  size: string;     // Total size at this price level
  orders: number;   // Number of orders at this price
}

Example Usage

Get Order Book for a Market

import { Clob, createConnectedWallet } from "@dicedhq/clob";

const wallet = createConnectedWallet({
  privateKey: process.env.PRIVATE_KEY,
  chain: "polygon",
});

const credentials = {
  key: process.env.POLYMARKET_API_KEY,
  secret: process.env.POLYMARKET_SECRET,
  passphrase: process.env.POLYMARKET_PASSPHRASE,
};

const client = new Clob({ wallet, credentials });

// Get order book for a specific token
const orderBook = await client.book.getOrderBook({
  tokenId: "0x1234567890abcdef..."
});

console.log("Order Book:");
console.log("Bids (Buy Orders):");
orderBook.bids.forEach(bid => {
  console.log(`  ${bid.price} - ${bid.size} shares (${bid.orders} orders)`);
});

console.log("\nAsks (Sell Orders):");
orderBook.asks.forEach(ask => {
  console.log(`  ${ask.price} - ${ask.size} shares (${ask.orders} orders)`);
});

Get Best Bid and Ask

const orderBook = await client.book.getOrderBook({
  tokenId: "0x1234567890abcdef..."
});

// Best bid (highest buy price)
const bestBid = orderBook.bids[0];
console.log(`Best bid: ${bestBid.price} for ${bestBid.size} shares`);

// Best ask (lowest sell price)
const bestAsk = orderBook.asks[0];
console.log(`Best ask: ${bestAsk.price} for ${bestAsk.size} shares`);

// Spread
const spread = parseFloat(bestAsk.price) - parseFloat(bestBid.price);
console.log(`Spread: ${spread.toFixed(4)}`);

Calculate Market Depth

const orderBook = await client.book.getOrderBook({
  tokenId: "0x1234567890abcdef..."
});

// Calculate total bid volume
const totalBidVolume = orderBook.bids.reduce(
  (sum, bid) => sum + parseFloat(bid.size),
  0
);

// Calculate total ask volume
const totalAskVolume = orderBook.asks.reduce(
  (sum, ask) => sum + parseFloat(ask.size),
  0
);

console.log(`Total bid volume: ${totalBidVolume}`);
console.log(`Total ask volume: ${totalAskVolume}`);
console.log(`Bid/Ask ratio: ${(totalBidVolume / totalAskVolume).toFixed(2)}`);

Find Liquidity at Price Level

const orderBook = await client.book.getOrderBook({
  tokenId: "0x1234567890abcdef..."
});

const targetPrice = "0.55";

// Find bids at or above target price
const bidsAbovePrice = orderBook.bids.filter(
  bid => parseFloat(bid.price) >= parseFloat(targetPrice)
);

const liquidityAbovePrice = bidsAbovePrice.reduce(
  (sum, bid) => sum + parseFloat(bid.size),
  0
);

console.log(`Liquidity at or above ${targetPrice}: ${liquidityAbovePrice} shares`);

Polling for Updates

Since the order book changes frequently, you may want to poll for updates:

async function pollOrderBook(tokenId: string, intervalMs: number = 5000) {
  while (true) {
    try {
      const orderBook = await client.book.getOrderBook({ tokenId });

      console.log(`[${new Date().toISOString()}]`);
      console.log(`Best bid: ${orderBook.bids[0]?.price || "N/A"}`);
      console.log(`Best ask: ${orderBook.asks[0]?.price || "N/A"}`);

      await new Promise(resolve => setTimeout(resolve, intervalMs));
    } catch (error) {
      console.error("Error fetching order book:", error);
      await new Promise(resolve => setTimeout(resolve, intervalMs));
    }
  }
}

// Start polling
pollOrderBook("0x1234567890abcdef...", 5000);

Error Handling

import { ApiError, NetworkError, ValidationError } from "@dicedhq/clob";

try {
  const orderBook = await client.book.getOrderBook({
    tokenId: "0x1234567890abcdef..."
  });
} catch (error) {
  if (error instanceof ValidationError) {
    console.error("Invalid token ID:", error.message);
  } else if (error instanceof NetworkError) {
    console.error("Network error:", error.message);
    // Retry logic
  } else if (error instanceof ApiError) {
    console.error("API error:", error.message);
  }
}

See Also

• CLOB Overview
• Markets
• Orders