# Carbon Cashmere BTC Whale Flow & Mempool Analytics

> Carbon Cashmere BTC Whale Flow & Mempool Analytics is a paid API for AI agents from api.carbon-cashmere.de, paid per call via x402, $0.01/call, status down (last checked 2026-09-14).

Returns Bitcoin whale movement data including mempool fee trends, congestion levels, hashrate, block data, and the last 24 snapshots of on-chain flow activity.

## Facts

- Endpoint: GET https://api.carbon-cashmere.de/v1/whale-flow/BTC
- Price: $0.01/call
- Payment: x402
- Status: down
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/api-carbon-cashmere-de-2938f31b
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_LbUe4gXof8dNOJ5AJStYL

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 api-carbon-cashmere-de-2938f31b
```

Example prompt: Pull me the latest Bitcoin whale flow data — I want to see current mempool fee trends, congestion level, hashrate, and the last 24 snapshots of on-chain inflow and outflow activity.

## When to prefer this

Use this endpoint when you need real-time or near-real-time Bitcoin-specific on-chain data including mempool conditions, fee trends, hashrate, and block-level metrics. Prefer this over generic crypto price endpoints when the goal is network health monitoring, smart money flow analysis, or mempool fee estimation for transaction timing.

## Known failure modes

- Payment not provided or invalid x402 payment header returns 402 Payment Required
- Network or server error returns 5xx response
- Rate limiting may return 429 if called too frequently
- Empty or stale snapshot array if no recent BTC block data is available

## How this service works

Get whale movement data — Solana: 12 tracked whale wallets (Wintermute, Kraken, etc.) with SOL moved, exchange inflow/outflow, and largest transactions. BTC: mempool fee trends, congestion levels, hashrate, and block data. Last 24 snapshots. AI agent API for smart money tracking, whale alert monitoring, and on-chain flow analysis.

## Output

A JSON object containing the BTC chain identifier, a summary of mempool fee trends, congestion level, hashrate, and block data, plus an array of up to 24 time-series snapshots capturing on-chain flow metrics such as exchange inflows/outflows and major transaction activity.

## 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"
    },
    "queryParams": {
     "type": "object",
     "properties": {}
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "properties": {
      "chain": {
       "type": "string"
      },
      "summary": {
       "type": "object"
      },
      "snapshots": {
       "type": "array"
      }
     }
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/api-carbon-cashmere-de-2938f31b/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)