# BaseWhale Oracle x402

> BaseWhale Oracle x402 is a paid API for AI agents from basewhale-x402.vercel.app, paid per call via x402, $0.02/call, status unknown (last checked 2026-09-18).

Returns real-time on-chain whale transactions and large transfers on Base Mainnet (Chain ID 8453), filtered by minimum USD value

## Facts

- Endpoint: GET https://basewhale-x402.vercel.app/v1/whales
- Price: $0.02/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-18
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/basewhale-oracle-x402-4a337923
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_TbnNE613UyV1TrU-lPQPF

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 basewhale-oracle-x402-4a337923
```

Example prompt: Show me the top 10 whale transactions on Base mainnet right now — only include transfers worth at least $50,000.

## When to prefer this

Choose this endpoint when you need real-time, on-chain large-transfer data specifically for Base Mainnet (Chain ID 8453). It is ideal for DeFi agents, trading bots, and market monitoring systems that need to detect whale activity programmatically with a low per-call cost of $0.02 USDC. Prefer this over general blockchain explorers when you need structured, filterable whale data via a simple API rather than raw block data.

## Known failure modes

- Payment not provided or invalid x402 payment header — returns 402 Payment Required
- Invalid input parameters (e.g. non-integer limit) — returns 400 Bad Request
- No whale transactions found meeting the minimum USD threshold — returns empty transactions array with whale_count of 0
- Upstream Base node unavailability causing stale or missing data
- Rate limiting if payment is not processed correctly

## How this service works

Real-Time On-Chain Whale & Large Transfer Oracle for Base Mainnet (Chain ID 8453), payable via x402.

## Output

Returns a JSON object containing the network name (Base), a timestamp, the count of whale transactions found, an array of individual whale transactions, and the total USD volume of all whale transactions in the result set.

## 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",
    "queryParams"
   ],
   "properties": {
    "type": {
     "const": "http"
    },
    "method": {
     "const": "GET"
    },
    "queryParams": {
     "type": "object",
     "title": "WhaleInput",
     "properties": {
      "limit": {
       "type": "integer",
       "title": "Limit",
       "default": 15,
       "maximum": 100,
       "minimum": 1
      },
      "blocks": {
       "type": "integer",
       "title": "Blocks",
       "default": 25,
       "maximum": 50,
       "minimum": 1
      },
      "min_usd": {
       "type": "number",
       "title": "Min Usd",
       "default": 25000,
       "maximum": 1000000000000000,
       "minimum": 0
      }
     },
     "additionalProperties": false
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "properties": {
    "type": {
     "const": "json"
    },
    "example": {
     "type": "object",
     "title": "WhaleResponse",
     "required": [
      "success",
      "network",
      "tracked_token",
      "valuation_source",
      "source",
      "fetched_at",
      "min_usd_filter",
      "latest_block",
      "blocks_scanned",
      "whale_transactions_found",
      "total_whale_volume_usd",
      "transactions",
      "timestamp"
     ],
     "properties": {
      "source": {
       "type": "string",
       "title": "Source"
      },
      "network": {
       "type": "string",
       "title": "Network"
      },
      "success": {
       "type": "boolean",
       "title": "Success"
      },
      "timestamp": {
       "type": "string",
       "title": "Timestamp"
      },
      "fetched_at": {
       "type": "string",
       "title": "Fetched At"
      },
      "latest_block": {
       "type": "integer",
       "title": "Latest Block"
      },
      "transactions": {
       "type": "array",
       "items": {
        "type": "object",
        "title": "Transfer",
        "required": [
         "tx_hash",
         "block_number",
         "token",
         "amount_atomic",
         "amount_tokens",
         "amount_usd",
         "from_address",
         "to_address"
        ],
        "properties": {
         "token": {
          "type": "string",
          "title": "Token"
         },
         "tx_hash": {
          "type": "string",
          "title": "Tx Hash"
    
… (truncated)
```

## Response schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "network": {
   "type": "string"
  },
  "timestamp": {
   "type": "string"
  },
  "whale_count": {
   "type": "integer"
  },
  "transactions": {
   "type": "array"
  },
  "total_whale_volume_usd": {
   "type": "number"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/basewhale-oracle-x402-4a337923/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from basewhale-x402.vercel.app](https://www.zero.xyz/host/basewhale-x402.vercel.app/llms.txt)