# Arkham x402 Transaction Lookup

> Arkham x402 Transaction Lookup is a paid API for AI agents from api.arkm.com, paid per call via x402, $0.4/call, status unknown (last checked 2026-09-14).

Fetches enriched on-chain transaction details by hash, including USD value, gas data, and Arkham entity labels for sender/receiver addresses.

## Facts

- Endpoint: POST https://api.arkm.com/x402/tx
- Price: $0.4/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/arkham-x402-transaction-lookup-525b80cb
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_IEcBsMCPtbp-44ChcPpTs

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 arkham-x402-transaction-lookup-525b80cb -d '<json body>'
```

Example prompt: Can you look up Ethereum transaction 0x5c504ed432cb51138bcf09aa5e8a410dd4a1e204ef84bfed1be16dfba1b22060 for me and tell me who sent it, who received it, the USD value, and whether Arkham has any labels on those addresses?

## When to prefer this

Choose this endpoint when you need enriched, Arkham-labeled transaction data — specifically when entity identification (who owns the sending/receiving address) matters alongside raw on-chain data. Prefer this over generic blockchain explorers when you need USD valuation, Arkham intelligence labels, and structured JSON output in a single pay-per-request call without managing a subscription.

## Known failure modes

- Invalid or malformed transaction hash returns an error
- Transaction hash not found on the specified chain returns empty or 404
- Network not supported returns an error
- Payment failure via x402 (insufficient USDC balance) blocks the request
- Rate limiting if too many requests are made in a short window

## How this service works

Get Arkham transaction details. $0.40 per call.

## Output

A JSON object containing full transaction metadata: chain, status (completed/pending/failed), transaction hash, block number, block hash, block timestamp, from/to addresses with Arkham entity labels (name, address, chain type), token symbol and ID, ETH price at time of transaction, USD value of the transfer, gas price, gas limit, gas used, receipt status, contract address (if applicable), and whether it was a mempool transaction.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "hash": {
   "anyOf": [
    {
     "type": "string"
    },
    {
     "type": "number"
    },
    {
     "type": "boolean"
    },
    {
     "type": "array",
     "items": {
      "anyOf": [
       {
        "type": "string"
       },
       {
        "type": "number"
       },
       {
        "type": "boolean"
       }
      ]
     }
    }
   ],
   "description": "The transaction hash to look up."
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "ethereum": {
   "fee": 1.05,
   "hash": "0x5c504ed432cb51138bcf09aa5e8a410dd4a1e204ef84bfed1be16dfba1b22060",
   "chain": "ethereum",
   "status": "completed",
   "tokenID": "ethereum",
   "ethPrice": 2.83162,
   "gasLimit": 21000,
   "gasPrice": 50000,
   "usdValue": 8.873447594e-14,
   "blockHash": "0x4e3a3754410177e6937ef1f84bba68ea139e8d1a2258c5f85db9f1cd715a1bdd",
   "toAddress": "0x5DF9B87991262F6BA471F09758CDE1c0FC1De734",
   "unitValue": 3.1337e-14,
   "blockNumber": 46147,
   "fromAddress": "0xA1E4380A3B1f749673E270229993eE55F35663b4",
   "isMempoolTx": false,
   "tokenSymbol": "ETH",
   "receiptStatus": 0,
   "blockTimestamp": "2015-08-07T03:30:33Z",
   "contractAddress": null,
   "enrichedToAddress": {
    "chain": "ethereum",
    "address": "0x5DF9B87991262F6BA471F09758CDE1c0FC1De734",
    "contract": false,
    "isUserAddress": false
   },
   "enrichedFromAddress": {
    "chain": "ethereum",
    "address": "0xA1E4380A3B1f749673E270229993eE55F35663b4",
    "contract": false,
    "arkhamLabel": {
     "name": "thanateros.eth",
     "address": "0xA1E4380A3B1f749673E270229993eE55F35663b4",
     "chainType": "evm"
    },
    "isUserAddress": false
   },
   "gasUsageByTransaction": 21000
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/arkham-x402-transaction-lookup-525b80cb/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.arkm.com](https://www.zero.xyz/host/api.arkm.com/llms.txt)