# Kronos Volatility API

> Kronos Volatility API is a paid API for AI agents from kronossignals.com, paid per call via x402, $0.02/call, status unknown (last checked 2026-09-15).

Returns annualized realized volatility term structure (7d and 30d) for a crypto asset, including Parkinson, Garman-Klass, and close-to-close estimators with percentile context and vol regime classification.

## Facts

- Endpoint: GET https://kronossignals.com/api/v1/volatility/%7Basset%7D
- Price: $0.02/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/kronos-volatility-api-72ef8a3a
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_halLy-p02gBDsjvVvcHE3

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 kronos-volatility-api-72ef8a3a
```

Example prompt: What's the current realized volatility for BTC-USD — give me the 7-day and 30-day annualized numbers, which estimator Kronos recommends, and whether we're in an elevated vol regime right now.

## When to prefer this

Choose this endpoint when you need multi-estimator realized volatility with historical percentile context for crypto assets — particularly when you need Parkinson or Garman-Klass high-low range estimators rather than simple close-to-close vol. Prefer this over generic price APIs when the use case is risk management, options pricing, regime detection, or vol-based position sizing. The term structure (7d vs 30d) and vol regime label make it more useful than a single-number vol figure.

## Known failure modes

- Unsupported asset symbol returns error or empty response
- Stale data if Binance feed is delayed — check as_of timestamp
- Malformed asset path parameter causes 4xx error
- Payment not processed (x402 flow failure) results in 402 response with no data
- Insufficient candles for a window if asset is newly listed

## How this service works

Paid market-intelligence API over x402

## Output

A JSON object containing: annualized realized volatility for 7d and 30d windows (close-to-close, Parkinson, Garman-Klass estimators), a recommended best estimator per window, volatility regime label (e.g. 'elevated'), full percentile context (current vol, historical min/max, sample count, window-high/low flags), data source attribution (Binance daily klines), and timestamp of the snapshot.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "properties": {
   "type": "string"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "note": "All estimates are annualized realized volatility using closed daily candles. Annualized by sqrt(252) trading-day convention.",
  "as_of": "2026-07-02T10:00:00.000Z",
  "asset": "BTC-USD",
  "source": "Binance daily klines (closed candles only)",
  "symbol": "BTCUSDT",
  "disclaimer": "Realized volatility from Binance daily OHLC. Historical; not a forecast. Not financial advice.",
  "term_structure": [
   {
    "note": "annualized realized volatility",
    "window": "7d",
    "n_candles": 7,
    "parkinson": 0.48,
    "percentile": 0.72,
    "vol_regime": "elevated",
    "garman_klass": 0.51,
    "best_estimator": "parkinson",
    "close_to_close": 0.54
   },
   {
    "note": "annualized realized volatility",
    "window": "30d",
    "n_candles": 30,
    "parkinson": 0.58,
    "percentile": 0.81,
    "vol_regime": "elevated",
    "garman_klass": 0.61,
    "best_estimator": "garman_klass",
    "close_to_close": 0.62
   }
  ],
  "vol_7d_annualized": 0.54,
  "percentile_context": [
   {
    "max": 1.05,
    "min": 0.22,
    "estimator": "parkinson",
    "percentile": 0.72,
    "vol_window": "7d",
    "current_vol": 0.48,
    "sample_count": 87,
    "is_window_low": false,
    "is_window_high": false
   },
   {
    "max": 0.98,
    "min": 0.28,
    "estimator": "parkinson",
    "percentile": 0.81,
    "vol_window": "30d",
    "current_vol": 0.58,
    "sample_count": 87,
    "is_window_low": false,
    "is_window_high": true
   }
  ],
  "vol_30d_annualized": 0.62
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/kronos-volatility-api-72ef8a3a/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from kronossignals.com](https://www.zero.xyz/host/kronossignals.com/llms.txt)