# Carbon & Cashmere Oracle Consensus 3-Way Price Feed (BTC)

> Carbon & Cashmere Oracle Consensus 3-Way Price Feed (BTC) is a paid API for AI agents from api.carbon-cashmere.de, paid per call via x402, $0.05/call, status down (last checked 2026-09-14).

Returns a 3-source consensus price for BTC from DIA, Pyth, and CoinGecko, including mean/median, pairwise spreads, and outlier detection.

## Facts

- Endpoint: GET https://api.carbon-cashmere.de/v1/oracle-consensus-3way/BTC
- Price: $0.05/call
- Payment: x402
- Status: down
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/carbon-cashmere-oracle-consensus-3-way-price-feed-btc-7a3f5a09
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_C1B3MzyWIwfC2V_G4lMzC

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-oracle-consensus-3-way-price-feed-btc-7a3f5a09
```

Example prompt: Pull the 3-way oracle consensus price for BTC right now — I want to see what DIA, Pyth, and CoinGecko are each reporting, which one is the outlier, and how wide the spread is between them.

## When to prefer this

Use this endpoint when you need a cross-validated, multi-oracle BTC price with outlier detection and spread analysis — especially for DeFi applications, risk checks, or any scenario where trusting a single price feed is insufficient. Prefer over single-source feeds when data integrity and oracle consensus quality matter.

## Known failure modes

- Coin symbol not supported — 404 or empty response
- One or more upstream oracles (DIA, Pyth, CoinGecko) may return stale data — timestamps may diverge significantly
- Payment failure via x402 — 402 response if USDC payment not attached
- Network timeout if any oracle source is slow to respond
- Malformed path parameter returns 400 or unexpected error

## How this service works

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

## Output

A JSON object containing per-source price quotes (with timestamps and confidence where available), a consensus block with mean USD, median USD, max spread pct, and the identified outlier source with its deviation percentage and absolute USD deviation, plus a pairwise spread array comparing every pair of sources.

## Request schema (JSON Schema)

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

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "coin": "BTC",
  "sources": [
   {
    "ts": "2026-05-09T21:31:56Z",
    "name": "DIA",
    "price": 80790.02
   },
   {
    "ts": "2026-05-09T21:25:03Z",
    "name": "Pyth",
    "price": 80785.39,
    "confidence": 19.22
   },
   {
    "ts": "2026-05-09T21:25:00Z",
    "name": "CoinGecko",
    "price": 80812
   }
  ],
  "consensus": {
   "outlier": {
    "name": "CoinGecko",
    "deviation_pct": 0.027,
    "deviation_abs_usd": 21.98
   },
   "mean_usd": 80795.8,
   "median_usd": 80790.02,
   "max_spread_pct": 0.033
  },
  "pairwise_spreads": [
   {
    "a": "DIA",
    "b": "Pyth",
    "spread_pct": 0.0057
   },
   {
    "a": "DIA",
    "b": "CoinGecko",
    "spread_pct": -0.0272
   },
   {
    "a": "Pyth",
    "b": "CoinGecko",
    "spread_pct": -0.0329
   }
  ]
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/carbon-cashmere-oracle-consensus-3-way-price-feed-btc-7a3f5a09/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)