# Carbon & Cashmere Open Interest History API – BTC

> Carbon & Cashmere Open Interest History API – BTC is a paid API for AI agents from api.carbon-cashmere.de, paid per call via x402, $0.02/call, status down (last checked 2026-09-15).

Returns historical open interest data for Bitcoin across exchanges, including daily series and aggregate stats like change percent and total USD value.

## Facts

- Endpoint: GET https://api.carbon-cashmere.de/v1/history/oi/BTC
- Price: $0.02/call
- Payment: x402
- Status: down
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/carbon-cashmere-open-interest-history-api-btc-6f84aef6
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_nQGtauhqCIR28x8xp9I-z

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-open-interest-history-api-btc-6f84aef6
```

Example prompt: Pull the last 7 days of Bitcoin open interest history from Carbon & Cashmere — I want to see the daily OI series and the overall change percent and total USD for the period.

## When to prefer this

Use this endpoint when you need historical open interest data specifically for Bitcoin across multiple exchanges, with per-exchange breakdowns (e.g. Binance) and aggregate stats. Prefer this over generic market data APIs when you need crypto-native OI analytics with a professional signal focus and time-series granularity.

## Known failure modes

- Invalid coin symbol returns error or empty result
- Unsupported time window may return partial or no series data
- Payment failure (x402) blocks the response if USDC payment is not processed
- Network or upstream data provider outage results in 5xx error
- Missing or malformed query parameters may return a 400 bad request

## How this service works

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

## Output

A JSON object containing the coin symbol (BTC), the number of days in the window, aggregate stats (change_pct, current_total_usd), and a daily time series array with timestamps, total OI in USD, and per-exchange OI (e.g. Binance) for each day.

## Request schema (JSON Schema)

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

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "coin": "BTC",
  "days": 7,
  "stats": {
   "change_pct": 2.1,
   "current_total_usd": 111000000000
  },
  "series": [
   {
    "ts": "2026-04-11T00:00:00Z",
    "total_oi_usd": 108500000000,
    "binance_oi_usd": 52000000000
   }
  ]
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/carbon-cashmere-open-interest-history-api-btc-6f84aef6/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)