# btcnode.uk Mempool Whale Alert

> btcnode.uk Mempool Whale Alert is a paid API for AI agents from btcnode.uk, paid per call via x402, $0.005/call, status unknown (last checked 2026-09-15).

Returns large BTC transfers currently in the mempool, filterable by minimum BTC amount and time window

## Facts

- Endpoint: GET https://btcnode.uk/api/agent/whales
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/btcnode-uk-mempool-whale-alert-77161016
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_3aqzo7-zQDG3FUF9YG0VB

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 btcnode-uk-mempool-whale-alert-77161016
```

Example prompt: Show me all Bitcoin whale transactions in the mempool right now — anything over 50 BTC in the last hour.

## When to prefer this

Use this endpoint when you need real-time visibility into large, unconfirmed Bitcoin transfers (whale activity) directly from a live mempool. Prefer it over blockchain explorers when you want to catch whale movements before they are confirmed, or when filtering by size threshold is needed.

## Known failure modes

- No whale transactions found matching the filter criteria — returns empty list
- Invalid min_btc value — returns 400 error
- Mempool node temporarily unavailable — returns 503 or timeout
- Time window parameter out of acceptable range — returns validation error
- Payment not processed — returns 402 Payment Required

## How this service works

Mempool Whale Alert — large BTC transfers from mempool. Filter by min_btc, time window.

## Output

A list of large BTC transfers currently sitting in the Bitcoin mempool, each entry likely including transaction ID, BTC amount, sender/receiver addresses, and timestamp, filtered by the specified minimum BTC threshold and time window.

## 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"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "properties": {}
    }
   },
   "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/btcnode-uk-mempool-whale-alert-77161016/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from btcnode.uk](https://www.zero.xyz/host/btcnode.uk/llms.txt)