# HTTPay Whale Tracker — Large Transfer Monitor on Base

> HTTPay Whale Tracker — Large Transfer Monitor on Base is a paid API for AI agents from httpay.xyz, paid per call via x402, $0.005/call, status unknown (last checked 2026-09-14).

Monitors and returns large token transfers (whale activity) for a given address on Base, tracking USDC, WETH, cbETH, and cbBTC with entity labels for known protocols.

## Facts

- Endpoint: POST https://httpay.xyz/api/whale-tracker
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/httpay-whale-tracker-large-transfer-monitor-on-base-fbca4704
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_lIhOGG2ZTuEqoakMoVxbl

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-whale-tracker-large-transfer-monitor-on-base-fbca4704 -d '<json body>'
```

Example prompt: Show me the last 10 large token transfers involving wallet 0x4200000000000000000000000000000000000006 on Base — I want to see if any known entities like Coinbase or Aave are moving big amounts of USDC or WETH.

## When to prefer this

Use this endpoint when you need to monitor or audit large on-chain token transfers (whale activity) for a specific Base address, especially when you want entity labels for known DeFi protocols without needing an API key or subscription — ideal for DeFi risk analysis, portfolio monitoring, or on-chain due diligence at low per-call cost.

## Known failure modes

- Invalid or malformed wallet address returns an error
- Limit parameter missing or invalid causes request rejection
- Address with no large transfers returns empty results
- Basescan API downtime may cause upstream failures
- Network or payment failure via x402 prevents call execution

## How this service works

Monitor large token transfers (whales) on Base. Tracks USDC, WETH, cbETH, cbBTC transfers above a USD threshold. Labels known entities (Coinbase, Aave, Uniswap, Aerodrome). Powered by Basescan.

## Output

A JSON response listing recent large token transfers (USDC, WETH, cbETH, cbBTC) above a USD threshold for the requested address, with entity labels for known protocols like Coinbase, Aave, Uniswap, and Aerodrome, powered by Basescan data.

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "description": "Monitor large token transfers (whales) on Base. Tracks USDC, WETH, cbETH, cbBTC transfers above a USD threshold. Labels known entities (Coinbase, Aave, Uniswap, Aerodrome). Powered by Basescan."
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/httpay-whale-tracker-large-transfer-monitor-on-base-fbca4704/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)