# Carbon & Cashmere Rolling Correlation API – BTC/SOL

> Carbon & Cashmere Rolling Correlation API – BTC/SOL is a paid API for AI agents from api.carbon-cashmere.de, paid per call via x402, $0.05/call, status unknown (last checked 2026-09-15).

Returns rolling correlation statistics between BTC and SOL, including current correlation value, trend, regime classification, and historical percentile over a configurable lookback window.

## Facts

- Endpoint: GET https://api.carbon-cashmere.de/v1/rolling-correlation/BTC-SOL
- Price: $0.05/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/carbon-cashmere-rolling-correlation-api-btc-sol-21acb51e
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_Pxbo6879SY942jF2iMPme

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 carbon-cashmere-rolling-correlation-api-btc-sol-21acb51e
```

Example prompt: What's the current rolling 30-day correlation between BTC and SOL — is it in a strongly positive regime or has it been drifting, and where does today's reading sit in the 90-day historical percentile?

## When to prefer this

Use this endpoint when you need a quantitative measure of how synchronized BTC and SOL price movements are over a rolling window, including regime classification and percentile context. Prefer this over generic price endpoints when you need correlation-based portfolio or diversification analysis, or when you want to know whether two assets are trending together or diverging.

## Known failure modes

- Unsupported or misspelled ticker pair returns an error or empty result
- Network timeout if the data provider is temporarily unavailable
- Payment failure (x402) if USDC balance is insufficient or wallet is not configured
- Rate limiting if the endpoint is called too frequently
- Invalid or missing window/lookback parameters may return default values or an error

## How this service works

Professional crypto market intelligence. Real-time prices, signals, and market scoring.

## Output

A JSON object containing the current correlation coefficient between BTC and SOL, a regime label (e.g. 'strongly_positive'), a trend label (e.g. 'stable'), the historical percentile of the current correlation, mean and standard deviation over the lookback period, the number of data points, and the window/lookback configuration used.

## Request schema (JSON Schema)

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

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "base": "BTC",
  "pair": "BTC-ETH",
  "_meta": {
   "disclaimer": "Informational research data only — not investment advice."
  },
  "quote": "ETH",
  "trend": "stable",
  "regime": "strongly_positive",
  "statistics": {
   "std_over_lookback": 0.08,
   "current_percentile": 0.68,
   "mean_over_lookback": 0.78
  },
  "data_points": 540,
  "window_days": 30,
  "lookback_days": 90,
  "current_correlation": 0.82
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/carbon-cashmere-rolling-correlation-api-btc-sol-21acb51e/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.carbon-cashmere.de](https://www.zero.xyz/host/api.carbon-cashmere.de/llms.txt)