# Solana (SOL) Volatility Density Endpoint

> Solana (SOL) Volatility Density Endpoint is a paid API for AI agents from solidus-x402.fly.dev, paid per call via x402, $0.05/call, status down (last checked 2026-09-15).

Returns the SOL volatility probability density using an EWMA+HAR blend with Student-t quantile hints, useful for risk sizing and options pricing.

## Facts

- Endpoint: GET https://solidus-x402.fly.dev/v1/density/SOL
- Price: $0.05/call
- Payment: x402
- Status: down
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/solana-sol-volatility-density-endpoint-5ae18106
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_U5vY0Fllq5qtBay0RwJ8C

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 solana-sol-volatility-density-endpoint-5ae18106
```

Example prompt: What's the current volatility density for SOL — I need the EWMA+HAR blended vol with the Student-t quantile hint so I can size my position properly before placing a Solana trade.

## When to prefer this

Choose this endpoint when you need a statistically grounded, model-blended volatility density for SOL rather than a raw spot price or implied vol scalar. Ideal when you need the full distributional shape (EWMA+HAR blend + Student-t tail behavior) for options pricing, VaR computation, or risk-aware position sizing on Solana. Prefer over generic price feeds when tail quantiles and distributional skew matter.

## Known failure modes

- Payment not included or insufficient USDC (402 Payment Required)
- Invalid or unsupported symbol path parameter (422 Unprocessable Entity)
- Upstream market data unavailable causing stale or missing density (503 Service Unavailable)
- Rate limiting if too many requests in a short window (429 Too Many Requests)

## How this service works

SOL vol density — EWMA+HAR vol blend + Student-t quantile hint (SIBYL doctrine, mean 0).

## Output

Returns a volatility probability density object for SOL, blending EWMA and HAR volatility models with a Student-t quantile hint. The output is centered at mean 0 and provides a statistical distribution of expected SOL volatility, useful for options pricing, risk sizing, and tail-risk assessment.

## 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",
      "HEAD",
      "DELETE"
     ],
     "type": "string"
    },
    "pathParams": {
     "type": "object",
     "required": [
      "symbol"
     ],
     "properties": {
      "symbol": {
       "enum": [
        "BTC",
        "ETH",
        "SOL",
        "XRP",
        "BNB",
        "DOGE",
        "AVAX",
        "LINK",
        "ARB",
        "OP"
       ],
       "type": "string",
       "default": null
      }
     }
    },
    "queryParams": {
     "type": "object",
     "properties": {},
     "additionalProperties": false
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/solana-sol-volatility-density-endpoint-5ae18106/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from solidus-x402.fly.dev](https://www.zero.xyz/host/solidus-x402.fly.dev/llms.txt)