# GET /api/mcp/data/vol-arb-scan

> Are there mispriced butterflies or skew trades on SPY right now?

Scans the chain of one ticker for butterflies priced below fair, skew trades between ATM and OTM IV, calendar-spread opportunities and put-call parity violations, with the edge for each.

- **Family:** Screeners (https://apexvol.com/developers/screeners-api)
- **Plan:** Pro and above. Every call needs `Authorization: Bearer avmcp_<token>`; tokens are issued to paid and trial accounts under Account, then API Access.
- **Units:** Option prices in dollars; IVs in percentage points (iv_unit); edge_pct in percent.
- **Basis:** Model fair values from the chain IV; each row states its strategy and type.
- **MCP tools:** `scan_volatility_arb`
- **Background:** https://apexvol.com/learn/volatility-arbitrage

## Parameters

| Name | In | Default | Range | Meaning |
|---|---|---|---|---|
| `ticker` | query | SPY | symbol | Which chain to scan. |

## Request

```bash
curl -H "Authorization: Bearer avmcp_YOUR_TOKEN" \
     "https://apexvol.com/api/mcp/data/vol-arb-scan"
```

## Response (captured 2026-09-08)

Real response, lists cut to the rows nearest the money. The envelope is `{"success": true, "data": ...}`.

```json
{
  "success": true,
  "data": {
    "butterfly_mispricings": [
      {
        "butterfly_cost": 0.655,
        "edge": "1326.7% potential return",
        "edge_pct": 1326.7176,
        "expiration": "2026-09-15",
        "lower_strike": 760.0,
        "max_profit": 9.345,
        "middle_strike": 765.0,
        "option_type": "CALL",
        "risk_reward": 14.2672,
        "strategy": "Buy call butterfly at 765.0",
        "ticker": "SPY",
        "type": "BUTTERFLY_VALUE",
        "upper_strike": 770.0
      },
      {
        "butterfly_cost": 0.765,
        "edge": "1107.2% potential return",
        "edge_pct": 1107.1895,
        "expiration": "2026-09-15",
        "lower_strike": 775.0,
        "max_profit": 9.235,
        "middle_strike": 780.0,
        "option_type": "CALL",
        "risk_reward": 12.0719,
        "strategy": "Buy call butterfly at 780.0",
        "ticker": "SPY",
        "type": "BUTTERFLY_VALUE",
        "upper_strike": 785.0
      },
      {
        "butterfly_cost": 0.77,
        "edge": "1098.7% potential return",
        "edge_pct": 1098.7013,
        "expiration": "2026-09-15",
        "lower_strike": 765.0,
        "max_profit": 9.23,
        "middle_strike": 770.0,
        "option_type": "CALL",
        "risk_reward": 11.987,
        "strategy": "Buy call butterfly at 770.0",
        "ticker": "SPY",
        "type": "BUTTERFLY_VALUE",
        "upper_strike": 775.0
      }
    ],
    "calendar_spreads": [],
    "put_call_parity_violations": [],
    "skew_trades": [
      {
        "atm_iv": 9.11,
        "atm_strike": 770.0,
        "edge": "12.5 IV points of skew",
        "expiration": "2026-09-15",
        "iv_unit": "percentage_points",
        "otm_iv": 21.58,
        "otm_strike": 710.0,
        "skew": 12.47,
        "skew_pct": 136.8825,
        "strategy": "Sell OTM put skew",
        "ticker": "SPY",
        "type": "PUT_SKEW_TRADE"
      },
      {
        "atm_iv": 10.1,
        "atm_strike": 770.0,
        "edge": "11.7 IV points of skew",
        "expiration": "2026-09-16",
        "iv_unit": "percentage_points",
        "otm_iv": 21.81,
        "otm_strike": 710.0,
        "skew": 11.71,
        "skew_pct": 115.9406,
        "strategy": "Sell OTM put skew",
        "ticker": "SPY",
        "type": "PUT_SKEW_TRADE"
      },
      {
        "call_iv": 14.46,
        "call_strike": 830.0,
        "edge": "7.3 IV points asymmetry",
        "expiration": "2026-09-16",
        "iv_unit": "percentage_points",
        "put_iv": 21.81,
        "put_strike": 710.0,
        "skew_asymmetry": 7.35,
        "strategy": "Sell put / Buy call",
        "ticker": "SPY",
        "type": "RISK_REVERSAL"
      }
    ],
    "success": true,
    "ticker": "SPY",
    "timestamp": "2026-09-08T08:07:56.079469",
    "total_opportunities": 9
  }
}
```

## Fields

- `butterfly_mispricings[].lower_strike, middle_strike, upper_strike, butterfly_cost, edge`: Butterflies.
- `skew_trades[].atm_iv, otm_iv, skew, strategy`: Skew trades.
- `calendar_spreads[], put_call_parity_violations[]`: The other checks.
- `total_opportunities`: Count.

## Errors

- `401`: no or revoked token
- `429`: Retry-After seconds
- `403`: Pro plan required
- `424`: data feed unavailable, retry
- Full list: https://apexvol.com/developers/errors

## Ask it in an MCP client

- Scan SPY for volatility arbitrage.
- Any mispriced butterflies on NVDA this week?
- Show skew trades on QQQ.

Conventions for units, bases and timestamps: https://apexvol.com/developers/conventions