Browse and filter Polymarket prediction market events with aggregated volume, liquidity, and trader data via Nansen.
What it does
This endpoint screens Polymarket prediction market events (groups of related markets) through the Nansen API. It returns aggregated metrics across all markets within each event, including total volume (24h, 1 week, 1 month, all-time), total liquidity, total open interest, unique trader counts, and nested per-market data with bid/ask prices and price changes.
The endpoint accepts POST requests with a JSON body supporting filters for search query, active/closed status, tags, liquidity range, volume thresholds, open interest bounds, neg-risk framework, end-date windows, and pagination. Results can be sorted by volume, liquidity, open interest, unique traders, or age. The API uses a credit-based system: 10 credits (free tier) or 1 credit (pro tier) per call, with an x402 pay-per-request option at $0.01 per call. Rate limits are enforced per-second and per-minute, reported via response headers.
Nansen is a blockchain analytics platform providing smart money intelligence, wallet profiling, and on-chain flow analysis. This specific endpoint is part of the Prediction Markets module, which covers Polymarket data decoded from on-chain Polygon events. Authentication is via an `apiKey` header. The endpoint returned HTTP 402 on probe, confirming it is live and supports the x402 payment protocol.
Capabilities
Use cases
- —Discover the most active Polymarket prediction market events by volume or liquidity
- —Filter prediction market events by tags (e.g., Crypto, Politics) and active/closed status
- —Monitor aggregated trading activity and trader counts across grouped prediction markets
- —Build dashboards showing top prediction market events with nested market-level detail
- —Programmatically screen for new or trending prediction market events
Fit
Best for
- —Agents or bots monitoring Polymarket event activity in real time
- —Researchers analyzing prediction market volume and liquidity trends
- —Trading desks screening for high-volume or high-liquidity prediction events
- —Applications building prediction market aggregator UIs
Not for
- —Non-Polymarket prediction platforms (only Polymarket data is covered)
- —Historical time-series analysis of individual market prices (use the OHLCV endpoint instead)
- —Free-text natural language research queries (use the Nansen Agent endpoints instead)
Quick start
curl -X POST https://api.nansen.ai/api/v1/prediction-market/event-screener \
-H 'Content-Type: application/json' \
-H 'apiKey: YOUR_API_KEY' \
-d '{"order_by":[{"field":"volume_24hr","direction":"DESC"}],"status":"active","pagination":{"page":1,"per_page":10}}'Example
Request
{
"tags": [],
"query": "",
"status": "active",
"order_by": [
{
"field": "volume_24hr",
"direction": "DESC"
}
],
"pagination": {
"page": 1,
"per_page": 10
},
"max_liquidity": -1,
"min_liquidity": -1,
"min_volume_24hr": -1,
"max_open_interest": -1,
"min_open_interest": -1
}Response
{
"data": [
{
"tags": [
"Politics"
],
"markets": [
{
"best_ask": 0.54,
"best_bid": 0.52,
"question": "Will candidate X win?",
"market_id": "654412",
"volume_24hr": 120000,
"open_interest": 1500000,
"last_trade_price": 0.53
}
],
"event_id": "12345",
"neg_risk": true,
"event_title": "US Presidential Election 2028",
"market_count": 5,
"total_volume": 15000000,
"total_liquidity": 800000,
"total_volume_1mo": 5000000,
"total_volume_1wk": 1200000,
"total_traders_24h": 412,
"total_volume_24hr": 250000,
"total_open_interest": 3500000
}
],
"pagination": {
"page": 1,
"per_page": 10,
"is_last_page": false
}
}Endpoint
Quality
Full OpenAPI 3.1 schema with detailed request/response models, clear pricing ($0.01 per call via x402), credit costs documented, and the endpoint confirmed live via 402 probe. Minor deductions: no crawled external docs beyond the API root, and component schemas for EventScreenerRequest/Response reference sub-schemas not fully expanded inline.
Warnings
- —No external documentation pages were reachable beyond the API root health check; all information is derived from the OpenAPI spec.
- —The probe returned 402 via HEAD method, confirming the endpoint is live but no sample response body was captured.
Citations
- —The event-screener endpoint costs 10 credits (free) or 1 credit (pro) per call, with x402 price of $0.01.https://api.nansen.ai
- —The endpoint is part of the Prediction Markets tag group and screens Polymarket events with aggregated volume, liquidity, and trader counts.https://api.nansen.ai
- —The API uses OpenAPI 3.1.0 and requires apiKey header authentication.https://api.nansen.ai