# HALOWERK Value-at-Risk Calculator

> HALOWERK Value-at-Risk Calculator is a paid API for AI agents from handel.halowerk.com, paid per call via x402, $0.005/call, status unknown (last checked 2026-10-17).

Computes historical (nearest-rank) or parametric (normal distribution) Value at Risk for a portfolio given caller-supplied return series and parameters

## Facts

- Endpoint: POST https://handel.halowerk.com/v1/rechner/value-at-risk?utm_source=zero.xyz
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-17
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/halowerk-value-at-risk-calculator-ff7fd12f
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_fATS3rAHn75FFqb9b5xDr

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 halowerk-value-at-risk-calculator-ff7fd12f -d '<json body>'
```

Example prompt: Calculate the historical Value at Risk for my portfolio worth $500,000 using these 250 daily returns I'm providing, at 99% confidence over a 1-day horizon.

## When to prefer this

Choose this endpoint when you need a pure computational VaR engine without any market data dependency — all prices and returns are supplied by the caller. Ideal for agents with their own historical or simulated return series who need a reproducible, formula-correct VaR figure (historical nearest-rank or parametric normal) without brokerage access, data subscriptions, or embedded assumptions. Prefer over full-stack risk platforms when auditability and caller-controlled inputs matter.

## Known failure modes

- Fewer than 2 returns supplied (minItems violation)
- Confidence level outside (0, 0.999999] range
- Horizon periods exceeding 1000 or below 1
- Portfolio cash value below 1e-12 or above 1e12
- Invalid method enum value (must be 'historical' or 'normal')
- Individual return values outside ±1e12 bounds
- Payment failure or insufficient USDC balance (x402)

## How this service works

Historischer oder parametrischer Value at Risk. Historisch Nearest-Rank für eine Periode. Parametrisch Normalverteilung mit Stichprobenstandardabweichung und unabhängigen gleichverteilten Perioden. Vorzeichen nicht abgeschnitten. Alle Zahlen, Kurse und Vorgaben liefert der Aufrufer. Keine eigenen Kursdaten, kein Brokerzugriff, keine Ausführung. Rechenwerkzeug, keine Anlageberatung, keine Empfehlung.

## Output

Returns the computed Value at Risk figure (not truncated in sign) as a numeric result for the specified method, confidence level, horizon, and portfolio cash value. No price data is fetched; all inputs are caller-supplied. The result is a pure risk metric, not investment advice.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "method": {
   "enum": [
    "historical",
    "normal"
   ],
   "type": "string"
  },
  "returns": {
   "type": "array",
   "items": {
    "type": "number",
    "maximum": 1000000000000,
    "minimum": -1000000000000
   },
   "maxItems": 5000,
   "minItems": 2
  },
  "confidence": {
   "type": "number",
   "maximum": 0.999999,
   "exclusiveMinimum": 0
  },
  "portfolio_cash": {
   "type": "number",
   "maximum": 1000000000000,
   "minimum": 1e-12
  },
  "horizon_periods": {
   "type": "integer",
   "maximum": 1000,
   "minimum": 1
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/halowerk-value-at-risk-calculator-ff7fd12f/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from handel.halowerk.com](https://www.zero.xyz/host/handel.halowerk.com/llms.txt)