# Base Chain Transaction Lookup (x402)

> Base Chain Transaction Lookup (x402) is a paid API for AI agents from kr-x402-mvp.kgy5612.workers.dev, paid per call via x402, $0.002/call, status unknown (last checked 2026-10-31).

Retrieves detailed on-chain transaction data for a given Base network transaction hash, including transfers, USDC flows, gas usage, and x402 payment verification.

## Facts

- Endpoint: GET https://kr-x402-mvp.kgy5612.workers.dev/api/chain/tx?utm_source=zero.xyz
- Price: $0.002/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-31
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/base-chain-transaction-lookup-x402-4d15cf10
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_BZnW8xHP8PGx1CFEOXl7o

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 base-chain-transaction-lookup-x402-4d15cf10
```

Example prompt: Can you look up Base transaction 0x3ea6d07f7e990ba4c2289487cd12ea41b6e13b48518fa38b24de2afd1df1d8ca and tell me whether it was a successful x402 USDC payment and how much USDC was received?

## When to prefer this

Use this endpoint when you need to verify or inspect a specific Base chain transaction — especially to confirm x402 micropayment settlement, check USDC transfer details, or validate on-chain state before releasing a resource. Prefer it over block explorers when you need structured, machine-readable output with x402 payment verification flags rather than human-readable HTML pages. It requires no API key and charges only $0.002 USDC per call via x402.

## Known failure modes

- Invalid or malformed transaction hash (not matching ^0x[0-9a-fA-F]{64}$) returns a validation error
- Transaction not found on Base returns a 404 or empty result
- Payment not yet confirmed may return payment_verified: false
- x402 payment of 0.002 USDC required per call; missing or failed payment returns HTTP 402
- Network congestion or RPC timeout may cause transient errors
- Providing expect_to or expect_usdc that don't match actual tx data returns payment_verified: false

## How this service works

Pay-per-call crypto microdata for trading/onchain AI agents via x402 (USDC on Base): Base gas, token risk, balances, multi-venue prices, Hyperliquid book/funding, kimchi premium. No API keys.

## Output

Returns a JSON object with the transaction's hash, sender, recipient, block number, chain, contract method called, success status, ETH fee, gas used, timestamp, number of confirmations, ETH value, a list of token transfers (including token address, amount, symbol, from/to), a map of USDC received per address, a payment_verified boolean, and an is_x402_settlement boolean.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "hash"
     ],
     "properties": {
      "hash": {
       "type": "string",
       "pattern": "^0x[0-9a-fA-F]{64}$",
       "examples": [
        "0x3ea6d07f7e990ba4c2289487cd12ea41b6e13b48518fa38b24de2afd1df1d8ca"
       ],
       "description": "Base tx hash"
      },
      "expect_to": {
       "type": "string",
       "pattern": "^0x[0-9a-fA-F]{40}$",
       "description": "Optional: payee you expect to receive USDC"
      },
      "expect_usdc": {
       "type": "number",
       "minimum": 0,
       "description": "Optional: minimum USDC amount expected (with expect_to)"
      }
     },
     "additionalProperties": false
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "to": "0xca11bde05977b3631167028862be2a173976ca11",
  "from": "0xc6699d2aada6c36dfea5c248dd70f9cb0235cb63",
  "hash": "0x3ea6d07f7e990ba4c2289487cd12ea41b6e13b48518fa38b24de2afd1df1d8ca",
  "block": 53220068,
  "chain": "base",
  "method": "aggregate3 (Multicall3)",
  "status": "success",
  "fee_eth": 6.5e-7,
  "gas_used": 92312,
  "timestamp": "2026-10-28T23:18:03Z",
  "transfers": [
   {
    "to": "0xe4be4d0bd82d8e68203deff81f79ede0529f2617",
    "from": "0xa1d1c0cf717402ff3651aa4873ccf96410b01978",
    "token": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "amount": 0.002,
    "symbol": "USDC"
   }
  ],
  "value_eth": 0,
  "confirmations": 21764,
  "usdc_received": {
   "0xe4be4d0bd82d8e68203deff81f79ede0529f2617": 0.002
  },
  "payment_verified": true,
  "is_x402_settlement": true
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/base-chain-transaction-lookup-x402-4d15cf10/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from kr-x402-mvp.kgy5612.workers.dev](https://www.zero.xyz/host/kr-x402-mvp.kgy5612.workers.dev/llms.txt)