# Delx Volatility Sample

> Delx Volatility Sample is a paid API for AI agents from api.delx.ai, paid per call via x402, $0.003/call, status unknown (last checked 2026-09-13).

Estimates descriptive sample volatility (annualized standard deviation) from caller-supplied period returns

## Facts

- Endpoint: POST https://api.delx.ai/api/v1/x402/volatility-sample
- Price: $0.003/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/delx-volatility-sample-4c8e632f
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_HLgh1NAidyAekeK5oQIK1

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 delx-volatility-sample-4c8e632f -d '<json body>'
```

Example prompt: Calculate the annualized sample volatility from these daily returns: [0.012, -0.008, 0.003, 0.021, -0.015, 0.007, -0.004] using 365 periods per year.

## When to prefer this

Choose this endpoint when you have your own historical return series and need a fast, deterministic, stateless sample volatility estimate without subscribing to a live market data feed. Ideal for signal preparation pipelines, backtesting workflows, or any agent that already holds tick or return data and needs annualized vol as a downstream input. Preferable over full market-data APIs when cost, latency, or data-privacy constraints apply.

## Known failure modes

- Empty or missing returns array returns an error
- Non-numeric values in the returns array cause a validation failure
- Invalid or zero periods_per_year may produce division errors or nonsensical results
- Insufficient data points (e.g. a single return) may yield undefined or degenerate volatility
- Payment failure via x402 on Base blocks execution

## How this service works

Estimate descriptive sample volatility from caller-supplied returns — call when estimating descriptive sample volatility from returns. Use on caller-supplied ticks/returns when agents need signal prep without a licensed live market feed (ottoai-class demand, first-party transform). Returns deterministic machine-readable JSON for $0.003 USDC via x402 on Base. Execution is first-party, local-only, stateless, and memory-only with no paid upstream, no input retention, and no claim of live chain tip…

## Output

Returns deterministic machine-readable JSON containing the computed sample volatility (annualized standard deviation) derived from the supplied returns array and annualization factor. The result is stateless, computed locally with no upstream dependencies.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "returns": {
   "type": "array",
   "description": "Caller-supplied period returns for sample volatility."
  },
  "periods_per_year": {
   "type": "number",
   "description": "Annualization factor (e.g. 365 for daily)."
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "mean": 0.00125,
  "count": 4,
  "schema": "delx/util-volatility-sample/v1",
  "advisory": "Descriptive sample volatility only.",
  "annualized_vol": 0.25609752,
  "standard_deviation": 0.01340476
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/delx-volatility-sample-4c8e632f/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.delx.ai](https://www.zero.xyz/host/api.delx.ai/llms.txt)