Polymarket order book

$0.01 per call · failed calls are never charged · no account or subscription: pay per call with a card key or USDC

Polymarket order book for one market outcome from the CLOB: bids and asks (price and size) up to 50 levels, best bid and ask, mid, spread and USD depth within 5 cents of the mid on each side. Give the market slug and outcome, or a CLOB token id. Use to check liquidity and slippage before a trade, or to read a sharper price than the last trade.

Guide: Polymarket API, prediction market odds

Run it free (25 free calls) Buy credits by card (from $1) Example result (JSON)

Try it with your own inputs

The market's Polymarket slug (from polymarket_markets) or its polymarket.com URL

Uses one of your 25 free calls. Nothing is charged, and a call that fails is not counted.

Inputs

NameTypeDescription
slugstringThe market's Polymarket slug (from polymarket_markets) or its polymarket.com URL
outcomestringOutcome name, e.g. Yes or No (default the first outcome)
token_idstringInstead of slug: the CLOB token id of one outcome
depthintegerLevels per side, 1-50 (default 10)

Request

Over HTTP, with a card key from /credits:

curl -H "Authorization: Bearer adt_…" "https://agent-data-tools.revmesh2074.workers.dev/polymarket/orderbook?slug=will-jd-vance-win-the-2028-republican-presidential-nomination"

Or one of your 25 free calls, no key:

curl "https://agent-data-tools.revmesh2074.workers.dev/polymarket/orderbook?slug=will-jd-vance-win-the-2028-republican-presidential-nomination&trial=1"

Without a key, the same URL answers 402 Payment Required with x402 and MPP terms, so an agent with a wallet pays per call in USDC (Base, Polygon, Arbitrum or Solana over x402; Base or Tempo over MPP) and retries.

Example result

{
  "question": "Will JD Vance win the 2028 Republican presidential nomination?",
  "slug": "will-jd-vance-win-the-2028-republican-presidential-nomination",
  "outcome": "Yes",
  "tokenId": "7213…",
  "conditionId": "0x19d2…",
  "bestBid": 0.946,
  "bestAsk": 0.95,
  "mid": 0.948,
  "spread": 0.004,
  "bidDepthUsd": 120000.5,
  "askDepthUsd": 9000.25,
  "bids": [
    {
      "price": 0.946,
      "size": 1200
    }
  ],
  "asks": [
    {
      "price": 0.95,
      "size": 800
    }
  ],
  "bookTime": "2026-11-05T16:40:00.000Z",
  "note": "Polymarket public data at call time; prices are the market's implied probability (0-1). Not financial advice."
}

From an AI agent (MCP)

Add the MCP server to Claude, Cursor or any MCP client. This tool is polymarket_orderbook, and the first 25 successful calls are free:

https://agent-data-tools.revmesh2074.workers.dev/mcp

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