# ioswarm Prediction Markets Feed

> ioswarm Prediction Markets Feed is a paid API for AI agents from ioswarm.io, paid per call via x402, $0.01/call, status unknown (last checked 2026-10-11).

Returns the most-traded prediction markets on Polymarket and Kalshi ranked by 24-hour volume, with market-implied probabilities, price changes, liquidity, and close dates

## Facts

- Endpoint: POST https://ioswarm.io/api/v1/feeds/prediction-markets?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-11
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/ioswarm-prediction-markets-feed-c301f3d4
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_MvM884NGWr10tT_b07B1l

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability ioswarm-prediction-markets-feed-c301f3d4 -d '<json body>'
```

Example prompt: Show me the top 20 most-traded prediction markets right now across both Polymarket and Kalshi — I want the current market-implied probabilities, 24-hour changes, and when each market closes.

## When to prefer this

Choose this endpoint when you need real-time, volume-ranked prediction market data from both Polymarket and Kalshi in a single call, especially when you want market-implied probabilities with 24-hour momentum data. Prefer this over scraping individual market pages or general news APIs when you specifically need structured probability, liquidity, and volume metrics for event-driven forecasting or trading research.

## Known failure modes

- Invalid date format returns error — must use RFC 3339 or YYYY-MM-DD
- Ticker filter with no matching markets returns empty results
- Section value outside 'polymarket' or 'kalshi' enum causes validation error
- Limit exceeding 200 or below 1 returns validation error
- Past edition date too far back may return no archived data
- Payment not received (x402) results in 402 Payment Required response

## How this service works

The most-traded prediction markets right now on Polymarket and Kalshi, ranked by 24-hour volume: the market-implied probability for each outcome, its 24-hour change, volume, liquidity and close date, with links. One call instead of paging two exchanges' APIs. Rebuilt every hour. $0.01 per call, no account. Free 24h-delayed sample: GET https://ioswarm.io/api/v1/feeds/prediction-markets/sample.

## Output

A ranked list of the most-traded prediction markets from Polymarket and/or Kalshi, including each market's name, ticker, market-implied probability for each outcome, 24-hour probability change, 24-hour trading volume, available liquidity, and market close date — optionally filtered by platform, keyword, or ticker symbol.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "q": {
   "type": "string",
   "maxLength": 80,
   "description": "Text filter."
  },
  "at": {
   "type": "string",
   "description": "Past edition: RFC 3339 or YYYY-MM-DD."
  },
  "date": {
   "type": "string",
   "description": "YYYY-MM-DD (UTC)."
  },
  "limit": {
   "type": "integer",
   "maximum": 200,
   "minimum": 1,
   "description": "Items per section."
  },
  "ticker": {
   "type": "string",
   "description": "Ticker/symbol filter."
  },
  "section": {
   "enum": [
    "polymarket",
    "kalshi"
   ],
   "type": "string",
   "description": "One section (default: all)."
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/ioswarm-prediction-markets-feed-c301f3d4/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from ioswarm.io](https://www.zero.xyz/host/ioswarm.io/llms.txt)