# AgentUtility Polymarket Markets Search API

> AgentUtility Polymarket Markets Search API is a paid API for AI agents from x402.agentutility.ai, paid per call via x402, $0.005/call, status unknown (last checked 2026-09-15).

Search and filter Polymarket prediction market listings by query, category, tag, liquidity, and sort order, returning questions, outcomes, implied prices, volume, and URLs.

## Facts

- Endpoint: POST https://x402.agentutility.ai/markets
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/agentutility-polymarket-markets-search-api-b72ef3ae
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_HPts-Lsvyx7wHS5iNUbX3

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 agentutility-polymarket-markets-search-api-b72ef3ae -d '<json body>'
```

Example prompt: Search Polymarket for active prediction markets about the 2026 US midterm elections — filter to politics category, sort by liquidity descending, and return the top 10 results with their implied prices and slugs.

## When to prefer this

Choose this endpoint when you need structured, filterable access to Polymarket prediction market data including implied probabilities and liquidity metrics. Prefer it over direct Polymarket web scraping when you need clean JSON output with sorting and filtering. Use it when an agent needs to inform a user about crowd-sourced event probabilities without executing any trades.

## Known failure modes

- No markets found matching the query or filters — returns empty list
- Invalid category or tag value — may return empty results or error
- Offset/limit out of range — returns empty results
- Polymarket gamma-api upstream outage — service unavailable error
- Malformed POST body — returns 400 bad request

## How this service works

Markets API / Polymarket markets / prediction markets list and search. Exact buyer-demand slug backed by Polymarket gamma-api public market data. Filter active/closed markets by query, category, tag, liquidity, sort order, limit, and offset. Returns questions, slugs, outcomes, implied prices, liquidity, volume, and URLs. Data-only; no trading or order routing.

## Output

Returns a list of prediction market objects, each containing the market question, slug, possible outcomes, implied prices per outcome, current liquidity, total volume, and a direct URL to the market on Polymarket. No trading or order execution is included.

## 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",
    "bodyType",
    "body"
   ],
   "properties": {
    "body": {
     "properties": {
      "tag": {
       "type": "string",
       "description": "Polymarket tag slug filter."
      },
      "limit": {
       "type": "number",
       "description": "1-100. Default 20."
      },
      "order": {
       "enum": [
        "volume24hr",
        "liquidity",
        "endDate",
        "startDate"
       ],
       "type": "string",
       "description": "Sort field: 'volume24hr', 'liquidity', 'endDate', or 'startDate'. Omit for default gamma-api order."
      },
      "query": {
       "type": "string",
       "description": "Free-text filter applied to question, description, and slug."
      },
      "active": {
       "type": "boolean",
       "description": "Default true."
      },
      "closed": {
       "type": "boolean",
       "description": "Default false."
      },
      "offset": {
       "type": "number",
       "description": "Pagination offset."
      },
      "category": {
       "type": "string",
       "description": "Filter by Polymarket category substring."
      },
      "ascending": {
       "type": "boolean",
       "description": "Sort direction when order is set. Default false (descending)."
      },
      "min_liquidity": {
       "type": "number",
       "description": "Minimum liquidity in USD."
      }
     }
    },
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "POST"
     ],
     "type": "string"
    },
    "bodyType": {
     "enum": [
      "json",
      "form-data",
      "text"
     ],
     "type": "string"
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "properties": {
      "count": {
       "type": "integer"
      },
      "markets": {
       "type": "array",
       "items": {
        "type": "object",
        "properties": {
         "question": {
          "type": "string"
         },
         "outcome_prices": {
          "type": "array",
          "items": {
           "type": "number"
          }
         }
        }
       }
      },
      "attribution": {
       "type": "string"
      }
 
… (truncated)
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "count": 20,
  "markets": [
   {
    "question": "Will X happen?",
    "outcome_prices": [
     0.42,
     0.58
    ]
   }
  ],
  "attribution": "Data: Polymarket gamma-api. https://polymarket.com"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/agentutility-polymarket-markets-search-api-b72ef3ae/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402.agentutility.ai](https://www.zero.xyz/host/x402.agentutility.ai/llms.txt)