> For the complete documentation index, see [llms.txt](https://docs.nansen.ai/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.nansen.ai/api/prediction-market/market-event-screener.md).

# Market Event Screener

### Data Freshness & Historical Coverage

For data freshness and historical coverage, see [Data Coverage by Chain](/api/data-coverage.md); this endpoint follows it except where noted below.

* Returns a **current, point-in-time snapshot** of market activity metrics (volume, liquidity, and trader counts) — these reflect the latest state within the standard live latency rather than a historical look-back.

## Get Prediction Market Event Screener

> Browse and filter Polymarket events (groups of related markets). Includes aggregated\
> volume, liquidity, and trader counts across all markets in each event.\
> \
> \*\*What it helps to answer:\*\*\
> \
> 1\. \*\*What are the most popular prediction market events?\*\*\
> 2\. \*\*How much total volume does an event have across all its markets?\*\*\
> 3\. \*\*Which events have the most active trading?\*\*

```json
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tags"},"min_liquidity":{"type":"number","minimum":-1,"title":"Min Liquidity","description":"Minimum liquidity filter (-1 = no filter)","default":-1},"max_liquidity":{"type":"number","minimum":-1,"title":"Max Liquidity","description":"Maximum liquidity filter (-1 = no limit)","default":-1},"max_unique_traders_24h":{"type":"integer","minimum":-1,"title":"Max Unique Traders 24H","description":"Maximum unique traders in 24h (-1 = no limit)","default":-1},"min_volume_24hr":{"type":"number","minimum":-1,"title":"Min Volume 24Hr","description":"Minimum 24h volume filter (-1 = no filter)","default":-1},"neg_risk":{"anyOf":[{"type":"boolean"}],"title":"Neg Risk","description":"Filter by neg-risk framework (null = no filter)"},"min_open_interest":{"type":"number","minimum":-1,"title":"Min Open Interest","description":"Minimum open interest filter (-1 = no filter)","default":-1},"max_open_interest":{"type":"number","minimum":-1,"title":"Max Open Interest","description":"Maximum open interest filter (-1 = no limit)","default":-1},"end_date_before":{"type":"string","maxLength":100,"title":"End Date Before","description":"Filter markets ending before this datetime (ISO 8601)","default":""},"end_date_after":{"type":"string","maxLength":100,"title":"End Date After","description":"Filter markets ending after this datetime (ISO 8601)","default":""},"pagination":{"$ref":"#/components/schemas/PaginationRequest"}},"additionalProperties":false,"type":"object","title":"EventScreenerRequest","description":"Request for event screener endpoint."},"SortOrder_ScreenerSortField_":{"properties":{"field":{"$ref":"#/components/schemas/ScreenerSortField","description":"Field to sort by"},"direction":{"$ref":"#/components/schemas/SortDirection","description":"Sort direction (ASC or DESC)"}},"type":"object","required":["field","direction"],"title":"SortOrder[ScreenerSortField]"},"ScreenerSortField":{"type":"string","enum":["volume_24hr","volume","volume_1wk","volume_1mo","liquidity","open_interest","unique_traders_24h","age_hours"],"title":"ScreenerSortField","description":"Valid sort fields for screener endpoints."},"SortDirection":{"type":"string","enum":["ASC","DESC"],"title":"SortDirection","description":"Enum for sort directions."},"MarketStatus":{"type":"string","enum":["active","closed",""],"title":"MarketStatus","description":"Valid status filters for screener endpoints."},"PaginationRequest":{"properties":{"page":{"type":"integer","minimum":1,"title":"Page","description":"Page number (1-based)","default":1},"per_page":{"type":"integer","maximum":1000,"minimum":1,"title":"Per Page","description":"Number of records per page (max 1000)","default":10}},"type":"object","title":"PaginationRequest","description":"Pagination parameters for API 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ID"},"event_title":{"anyOf":[{"type":"string"}],"title":"Event Title","description":"Event title"},"tags":{"anyOf":[{"items":{"type":"string"},"type":"array"}],"title":"Tags","description":"Event tags"},"neg_risk":{"anyOf":[{"type":"boolean"}],"title":"Neg Risk","description":"Uses neg-risk framework"},"market_count":{"anyOf":[{"type":"integer"}],"title":"Market Count","description":"Number of markets"},"total_volume":{"anyOf":[{"type":"number"}],"title":"Total Volume","description":"Total volume (USD)"},"total_volume_24hr":{"anyOf":[{"type":"number"}],"title":"Total Volume 24Hr","description":"Total 24h volume (USD)"},"total_volume_1wk":{"anyOf":[{"type":"number"}],"title":"Total Volume 1Wk","description":"Total 1 week volume (USD)"},"total_volume_1mo":{"anyOf":[{"type":"number"}],"title":"Total Volume 1Mo","description":"Total 1 month volume (USD)"},"total_liquidity":{"anyOf":[{"type":"number"}],"title":"Total Liquidity","description":"Total liquidity (USD)"},"total_open_interest":{"anyOf":[{"type":"number"}],"title":"Total Open Interest","description":"Total open interest (USD)"},"total_volume_change_pct":{"anyOf":[{"type":"number"}],"title":"Total Volume Change Pct","description":"Total volume change percentage"},"total_traders_24h":{"anyOf":[{"type":"integer"}],"title":"Total Traders 24H","description":"Total unique traders in 24h"},"max_age_hours":{"anyOf":[{"type":"number"}],"title":"Max Age Hours","description":"Max market age in hours"},"top_market_id":{"anyOf":[{"type":"string"}],"title":"Top Market Id","description":"Top market by 24h volume"},"top_market_question":{"anyOf":[{"type":"string"}],"title":"Top Market Question","description":"Top market question"},"top_market_volume_24hr":{"anyOf":[{"type":"number"}],"title":"Top Market Volume 24Hr","description":"Top market 24h volume"},"markets":{"anyOf":[{"items":{"$ref":"#/components/schemas/EventScreenerMarket"},"type":"array"}],"title":"Markets","description":"Nested 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```


---

# Agent Instructions
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## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter:

```
GET https://docs.nansen.ai/api/prediction-market/market-event-screener.md?ask=<question>&goal=<endgoal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal.

The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.