# NBA Cross-Venue Championship Odds Gap (Polymarket vs Kalshi)

> NBA Cross-Venue Championship Odds Gap (Polymarket vs Kalshi) is a paid API for AI agents from nba-odds-gap.relayhop.workers.dev, paid per call via x402, $0.05/call, status unknown (last checked 2026-09-15).

Returns ranked list of 2026 NBA championship title implied-probability divergences between Polymarket and Kalshi, sorted by absolute gap size.

## Facts

- Endpoint: GET https://nba-odds-gap.relayhop.workers.dev/v1/nba/cross-venue-signals
- Price: $0.05/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/nba-odds-gap-relayhop-workers-dev-0a14dad8
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_6LxeqAnUuBXaDnKqAmPww

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 nba-odds-gap-relayhop-workers-dev-0a14dad8
```

Example prompt: Show me the top 3 NBA teams where Polymarket and Kalshi disagree most on 2026 championship odds — I want to see which markets are most out of sync right now.

## When to prefer this

Use this endpoint when you need a pre-computed, ranked comparison of NBA championship odds divergence across Polymarket and Kalshi simultaneously — rather than querying each prediction market separately and computing gaps yourself. Ideal for agents doing cross-venue arbitrage analysis, prediction market research, or sports analytics without needing API keys.

## Known failure modes

- page out of range (must be 1-50) returns error or empty result
- per_page exceeds cap of 3 returns capped or error response
- upstream Polymarket Gamma or Kalshi API unavailable causes stale or missing data
- payment of 0.05 USDC not provided returns 402 Payment Required
- no matching cross-listed NBA markets found returns empty signals list

## How this service works

NBA championship odds gap: Polymarket vs Kalshi implied-probability divergence on the same 2026 NBA title outcomes, ranked by |gap|. Query: ?page=1-50&per_page=1-3. Sources: Polymarket Gamma + Kalshi public API + ESPN (all free, keyless).

## Output

A ranked list (up to 3 per page, pages 1-50) of 2026 NBA title outcomes showing each team's implied probability on Polymarket and Kalshi, the absolute gap between them, and rank by divergence size — useful for spotting cross-market inefficiencies.

## Example request

```json
{
 "input": {
  "page": "1",
  "per_page": "3"
 }
}
```

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "properties": {
    "page": {
     "in": "query",
     "type": "string",
     "description": "ranked page 1-50 (default 1)"
    },
    "per_page": {
     "in": "query",
     "type": "string",
     "description": "signals per page 1-3, cap 3 (default 3)"
    }
   }
  },
  "output": {
   "type": "object"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/nba-odds-gap-relayhop-workers-dev-0a14dad8/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from nba-odds-gap.relayhop.workers.dev](https://www.zero.xyz/host/nba-odds-gap.relayhop.workers.dev/llms.txt)