# BlockRun Polymarket Open Interest Lookup

> BlockRun Polymarket Open Interest Lookup is a paid API for AI agents from blockrun.ai, paid per call via x402, $0.0085/call, status unknown (last checked 2026-09-15).

Fetches open interest data for a specific Polymarket prediction market condition via the BlockRun routing and payment layer.

## Facts

- Endpoint: GET https://blockrun.ai/api/v1/surf/prediction-market/polymarket/open-interest
- Price: $0.0085/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/blockrun-polymarket-open-interest-lookup-6c69a7ad
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_MY9-WoBAvBUxP74gHlVJf

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 blockrun-polymarket-open-interest-lookup-6c69a7ad
```

Example prompt: What's the current open interest for Polymarket condition 0xabc123def456? I want to know how much liquidity is locked in that market.

## When to prefer this

Use this endpoint when you need on-chain open interest data specifically from Polymarket and are operating within a BlockRun-enabled agent stack that handles x402 micropayments in USDC. Prefer this over scraping Polymarket directly or using other prediction market APIs when you need programmatic, agent-friendly access with built-in payment settlement.

## Known failure modes

- Missing or invalid condition_id returns an error or empty result
- Condition ID references a closed or non-existent market
- Payment failure via x402 protocol prevents the call from completing
- Rate limiting or upstream Polymarket API unavailability
- Malformed condition_id string format rejected by the API

## How this service works

Pay for the outcome. One endpoint for every model, tool and data source an agent needs — each call priced before it runs, at the best value per dollar. 103 models and 100 data and tool APIs.

## Output

Returns open interest data for the specified Polymarket condition, including the total value of open positions and related market metrics, allowing agents to assess liquidity and market depth for a given prediction market event.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "condition_id": {
   "type": "string",
   "description": "Required query param"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/blockrun-polymarket-open-interest-lookup-6c69a7ad/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from blockrun.ai](https://www.zero.xyz/host/blockrun.ai/llms.txt)