# httpay.xyz Whale Alert Monitor

> httpay.xyz Whale Alert Monitor is a paid API for AI agents from httpay.xyz, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-14).

Monitors real-time large transfers on Base blockchain for USDC, WETH, and cbBTC, returning whale movements above a specified USD threshold over the last N blocks

## Facts

- Endpoint: POST https://httpay.xyz/api/whale-alerts
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/httpay-xyz-ebc02cbd
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_DNdT3_ERLc98AhTHPmMq8

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 httpay-xyz-ebc02cbd -d '<json body>'
```

Example prompt: Show me the top 20 whale transfers on Base from the last 50 blocks where at least $10,000 in USDC moved — I want to see who's pushing big money around right now.

## When to prefer this

Use this endpoint when you need real-time on-chain whale activity specifically on the Base network for USDC, WETH, or cbBTC, and want to filter by minimum USD transfer size over recent blocks. Prefer this over general block explorers when you need structured, pre-filtered large-transfer data without parsing raw transactions.

## Known failure modes

- Invalid token symbol returns an error or empty result
- minUsd value too high returns empty list with no matches
- Limit exceeding API maximum returns truncated or error response
- Base RPC unavailability causes timeout or 503
- Payment of 0.01 USDC not received returns 402 Payment Required

## How this service works

Real-time large transfer monitoring on Base — track whale movements for USDC, WETH, and cbBTC over the last N blocks. Params: ?minUsd=10000&token=USDC&limit=20

## Output

A list of large transfer events on Base matching the specified token and minimum USD threshold, including transaction hashes, sender/recipient addresses, transfer amounts in USD, token type, and block numbers.

## Example request

```json
{
 "limit": 20,
 "blocks": 50,
 "minUsd": 10000,
 "tokens": [
  "USDC",
  "WETH",
  "cbBTC"
 ]
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "description": "Real-time large transfer monitoring on Base — track whale movements for USDC, WETH, and cbBTC over the last N blocks. Params: ?minUsd=10000&token=USDC&limit=20"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/httpay-xyz-ebc02cbd/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from httpay.xyz](https://www.zero.xyz/host/httpay.xyz/llms.txt)