# Cross-Venue BTC/ETH Futures-Spot Basis API

> Cross-Venue BTC/ETH Futures-Spot Basis API is a paid API for AI agents from nonvisceral-eloisa-mousily.ngrok-free.dev, paid per call via x402, $0.02/call, status unknown (last checked 2026-09-14).

Returns per-venue and aggregated futures-spot basis, funding rates, and contango/backwardation verdict for BTC and ETH across Binance, Bybit, and OKX

## Facts

- Endpoint: GET https://nonvisceral-eloisa-mousily.ngrok-free.dev/api/futures-spot-basis
- Price: $0.02/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/cross-venue-btc-eth-futures-spot-basis-api-16c64845
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_GL2y-0Vx-6UM90hZwAa6J

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 cross-venue-btc-eth-futures-spot-basis-api-16c64845
```

Example prompt: What's the current BTC and ETH perp-vs-spot basis across Binance, Bybit, and OKX right now — are they in contango or backwardation, and is there a meaningful cash-and-carry arb signal?

## When to prefer this

Choose this endpoint when you need a cross-venue, multi-symbol view of the perp-vs-spot basis and funding rates in a single call rather than polling each exchange individually. It is especially valuable for cash-and-carry arbitrage signal detection, cross-venue dispersion analysis, and funding-rate hedging cost estimation across BTC and ETH simultaneously. Prefer it over single-venue feeds when venue-to-venue discrepancies matter or when you want a machine-readable contango/backwardation verdict without building your own aggregation logic.

## Known failure modes

- One or more upstream venues (Binance/Bybit/OKX) unreachable — n_venues_reachable may be less than 3, reducing aggregate reliability
- Stale data if upstream exchange APIs are slow or rate-limiting
- No query parameters required so no input validation errors expected
- ngrok free-tier URL may have uptime or rate-limit constraints
- Payment failure (x402) if USDC balance is insufficient for the $0.02 per-call fee

## How this service works

Cross-venue BTC + ETH perp-vs-spot basis across Binance/Bybit/OKX. Per-venue mark/spot/basis/basis_bps/fundingRate/fundingRate_apr_pct, per-symbol aggregate_basis, max_dispersion_bps, avg_funding_apr_pct, verdict (contango>+5bps / flat / backwardation<-5bps). Cash-and-carry arbitrage signal beyond single-venue feeds.

## Output

A JSON object keyed by symbol (BTC, ETH), each containing per-venue data (mark price, spot price, basis, basis_bps, funding rate, funding rate APR %), plus aggregate metrics: aggregate_basis, max_dispersion_bps, avg_funding_apr_pct, number of venues reached, venues used, and a verdict string indicating contango (>+5bps), flat, or backwardation (<-5bps). Also includes a top-level source and updated_at timestamp.

## 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"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "properties": {}
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "properties": {
      "source": {
       "type": "string"
      },
      "per_symbol": {
       "type": "object",
       "description": "Keyed by symbol (BTC, ETH). per_venue + aggregate_basis + max_dispersion_bps + avg_funding_apr_pct + n_venues_reachable + venues_used + verdict."
      },
      "updated_at": {
       "type": "string"
      }
     }
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/cross-venue-btc-eth-futures-spot-basis-api-16c64845/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from nonvisceral-eloisa-mousily.ngrok-free.dev](https://www.zero.xyz/host/nonvisceral-eloisa-mousily.ngrok-free.dev/llms.txt)