# 2s.io Prediction Market Cross-Venue Search

> 2s.io Prediction Market Cross-Venue Search is a paid API for AI agents from 2s.io, paid per call via x402, $0.012/call, status unknown (last checked 2026-09-15).

Searches prediction market questions across Polymarket, Kalshi, and Limitless Exchange simultaneously, returning live prices, volume, and URLs for each matching market.

## Facts

- Endpoint: GET https://2s.io/api/predict/search
- Price: $0.012/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/2s-io-prediction-market-cross-venue-search-25893a7b
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_AOljIgqTq34ePvGgDI_yg

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 2s-io-prediction-market-cross-venue-search-25893a7b
```

Example prompt: Search prediction markets across Polymarket, Kalshi, and Limitless for 'Fed rate cut' — only open markets, up to 10 results per venue — and show me the current YES price and volume for each.

## When to prefer this

Use this endpoint when you need to find prediction markets about a real-world topic across multiple venues in a single call, especially when comparing odds or liquidity across Polymarket, Kalshi, and Limitless simultaneously. Prefer this over venue-specific APIs when you don't know which venue has the best market for a given question, or when you want to aggregate and compare prices in one step. It requires no API key and costs a flat $0.0048 USDC per call.

## Known failure modes

- Missing required 'q' parameter returns a 400 error
- Query shorter than 2 characters or longer than 120 characters is rejected
- No matching markets found returns an empty results array
- One or more venues may be unavailable, returning partial results
- Invalid 'status' enum value (not 'open' or 'closed') returns a 400 error
- Limit value outside 1–50 range is rejected

## How this service works

Cross-venue prediction-market keyword search across Polymarket, Kalshi, and Limitless Exchange in one call. Pass q (required); filter by status (open/closed) and cap per-venue with limit. Each hit is tagged with its venue and returns the question, live YES/NO price (0-1 implied probability), USD volume, close date, and the venue URL — for finding the same real-world question wherever it trades. Read-only, keyless.

## Output

A list of market hits, each tagged with venue (Polymarket, Kalshi, or Limitless), the full market question text, live YES and NO prices as implied probabilities (0–1), USD trading volume, market close date, and the direct URL to that market on its venue.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method",
    "queryParams"
   ],
   "properties": {
    "type": {
     "const": "http"
    },
    "method": {
     "const": "GET"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "q"
     ],
     "properties": {
      "q": {
       "type": "string",
       "maxLength": 120,
       "minLength": 2,
       "description": "Keyword(s) to search market questions for."
      },
      "limit": {
       "type": "integer",
       "maximum": 50,
       "minimum": 1,
       "description": "Max results per venue (default 15)."
      },
      "status": {
       "enum": [
        "open",
        "closed"
       ],
       "type": "string",
       "description": "Filter by market status."
      }
     },
     "additionalProperties": false
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/2s-io-prediction-market-cross-venue-search-25893a7b/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from 2s.io](https://www.zero.xyz/host/2s.io/llms.txt)