Polymarket API, prediction market odds

From $0.01 per successful call · failed calls are never charged · no account needed · Markdown version: /guides/polymarket-api.md

Polymarket prediction markets: the most traded open markets by 24-hour volume, or the markets matching a search, each with outcome prices (implied probability), best bid and ask, last trade, day change, volume, liquidity, end date, slug and CLOB token ids. Use to get the odds on an election, sports, crypto or news event, or to find a market before reading its order book.

Polymarket markets, odds $0.01

Polymarket prediction markets: the most traded open markets by 24-hour volume, or the markets matching a search, each with outcome prices (implied probability), best bid and ask, last trade, day change, volume, liquidity, end date, slug and CLOB token ids. Use to get the odds on an election, sports, crypto or news event, or to find a market before reading its order book.

Inputs: q: Optional search, e.g. bitcoin, election, fed rates; without it the top markets by 24h volume; limit: Markets to return, 1-20 (default 10); closed: true for resolved or closed markets instead of open ones.

Free first (25 successful calls per caller, no key):

curl "https://agent-data-tools.revmesh2074.workers.dev/polymarket/markets?q=bitcoin&trial=1"

With a card key from /credits, in a header or, when your client can only fetch a URL, in the URL:

curl -H "Authorization: Bearer adt_…" "https://agent-data-tools.revmesh2074.workers.dev/polymarket/markets?q=bitcoin"
curl "https://agent-data-tools.revmesh2074.workers.dev/polymarket/markets?q=bitcoin&api_key=adt_…"

Without a key the same URL answers 402 Payment Required with x402 and MPP terms, so a wallet client pays USDC per call and retries. Over MCP (https://agent-data-tools.revmesh2074.workers.dev/mcp) this tool is polymarket_markets.

Example result
{
  "query": "bitcoin",
  "closed": false,
  "count": 1,
  "markets": [
    {
      "question": "Will the price of Bitcoin be above $72,000 on November 5?",
      "slug": "bitcoin-above-72k-on-november-5-2026",
      "conditionId": "0x…",
      "outcomes": [
        {
          "name": "Yes",
          "price": 0.9955,
          "tokenId": "7755…"
        },
        {
          "name": "No",
          "price": 0.0045,
          "tokenId": "8888…"
        }
      ],
      "volume24h": 98817.32,
      "volume": 250000.5,
      "liquidity": 40000,
      "bestBid": 0.995,
      "bestAsk": 0.996,
      "lastTradePrice": 0.996,
      "dayChange": 0.01,
      "endDate": "2026-11-05T17:00:00Z",
      "active": true,
      "closed": false,
      "url": "https://polymarket.com/event/bitcoin-above-on-november-5-2026"
    }
  ],
  "note": "Polymarket public data at call time; prices are the market's implied probability (0-1). Not financial advice.",
  "checkedAt": "2026-11-05T16:40:00.000Z"
}

Tool page, inputs and limits

Prediction markets, Polymarket events $0.01

Polymarket events (one question with one or several markets, such as an election with many candidates): the busiest open events by 24-hour volume or those matching a search, with volume, liquidity, end date, tags, the number of open markets and the five leading outcomes by price. Use to see who leads a multi-candidate market or to browse what is being traded now.

Inputs: q: Optional search, e.g. president 2028; without it the busiest events by 24h volume; limit: Events to return, 1-10 (default 5).

Free first (25 successful calls per caller, no key):

curl "https://agent-data-tools.revmesh2074.workers.dev/polymarket/events?q=president&trial=1"

With a card key from /credits, in a header or, when your client can only fetch a URL, in the URL:

curl -H "Authorization: Bearer adt_…" "https://agent-data-tools.revmesh2074.workers.dev/polymarket/events?q=president"
curl "https://agent-data-tools.revmesh2074.workers.dev/polymarket/events?q=president&api_key=adt_…"

Without a key the same URL answers 402 Payment Required with x402 and MPP terms, so a wallet client pays USDC per call and retries. Over MCP (https://agent-data-tools.revmesh2074.workers.dev/mcp) this tool is polymarket_events.

Example result
{
  "query": "president",
  "count": 1,
  "events": [
    {
      "title": "Republican Presidential Nominee 2028",
      "slug": "republican-presidential-nominee-2028",
      "url": "https://polymarket.com/event/republican-presidential-nominee-2028",
      "endDate": "2028-11-08T04:59:00Z",
      "volume24h": 2470204.52,
      "volume": 727850358.28,
      "liquidity": 32474302.97,
      "tags": [
        "Politics"
      ],
      "openMarkets": 128,
      "leading": [
        {
          "title": "J.D. Vance",
          "slug": "will-jd-vance-win-the-2028-republican-presidential-nomination",
          "yesPrice": 0.52,
          "volume24h": 300000
        }
      ]
    }
  ],
  "note": "Polymarket public data at call time; prices are the market's implied probability (0-1). Not financial advice.",
  "checkedAt": "2026-11-05T16:40:00.000Z"
}

Tool page, inputs and limits

Polymarket order book $0.01

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.

Inputs: slug: The market's Polymarket slug (from polymarket_markets) or its polymarket.com URL; outcome: Outcome name, e.g. Yes or No (default the first outcome); token_id: Instead of slug: the CLOB token id of one outcome; depth: Levels per side, 1-50 (default 10).

Free first (25 successful calls per caller, no key):

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

With a card key from /credits, in a header or, when your client can only fetch a URL, in the URL:

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

Without a key the same URL answers 402 Payment Required with x402 and MPP terms, so a wallet client pays USDC per call and retries. Over MCP (https://agent-data-tools.revmesh2074.workers.dev/mcp) this tool is polymarket_orderbook.

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."
}

Tool page, inputs and limits

Polymarket price history $0.01

Polymarket price history of one market outcome from the CLOB: time and price points over the last hour, 6 hours, day, week, month or all time, with first, last, change, high and low. Give the market slug and outcome, or a CLOB token id. Use to chart how the odds moved, spot a swing after news, or backtest a signal.

Inputs: slug: The market's Polymarket slug (from polymarket_markets) or its polymarket.com URL; outcome: Outcome name, e.g. Yes or No (default the first outcome); token_id: Instead of slug: the CLOB token id of one outcome; interval: 1h, 6h, 1d, 1w (default), 1m or max.

Free first (25 successful calls per caller, no key):

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

With a card key from /credits, in a header or, when your client can only fetch a URL, in the URL:

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

Without a key the same URL answers 402 Payment Required with x402 and MPP terms, so a wallet client pays USDC per call and retries. Over MCP (https://agent-data-tools.revmesh2074.workers.dev/mcp) this tool is polymarket_price_history.

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…",
  "interval": "1d",
  "points": 24,
  "first": 0.9625,
  "last": 0.948,
  "change": -0.0145,
  "high": 0.9625,
  "low": 0.919,
  "history": [
    {
      "time": "2026-11-04T16:00:22.000Z",
      "price": 0.9625
    }
  ],
  "note": "Polymarket public data at call time; prices are the market's implied probability (0-1). Not financial advice."
}

Tool page, inputs and limits

Questions

How do I pay?

Each successful call costs the tool's price; failed calls are not charged. The first 25 calls are free. Then pay with card credits from $1 (the key goes in an Authorization header or as api_key= in the URL) or per call in USDC over x402 or MPP. No account is needed.