# SendCheck EVM Address Pre-Send Verifier

> SendCheck EVM Address Pre-Send Verifier is a paid API for AI agents from sendcheck-x402.pennyforgeorg.workers.dev, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-15).

Verifies an EVM address before sending crypto by checking EIP-55 checksum, wallet-vs-contract classification, outgoing activity, token balances, and issuing a safety verdict

## Facts

- Endpoint: POST https://sendcheck-x402.pennyforgeorg.workers.dev/check
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/sendcheck-evm-address-pre-send-verifier-62528bdb
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_-cgz73kchK02zDtEvQyzS

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 sendcheck-evm-address-pre-send-verifier-62528bdb -d '<json body>'
```

Example prompt: Before I send funds, run a SendCheck on 0x9504A5939AB5be2B2B1F8beA7D7ebeCcd96c485D on Base — tell me if it's a real wallet, whether it's ever sent transactions, and whether it's safe to send to.

## When to prefer this

Choose SendCheck when you need a quick, multi-signal pre-send safety assessment of a single EVM address on a supported chain (Base, Ethereum, Arbitrum, Optimism, Polygon) and want structured verdict output including checksum, wallet/contract classification, activity history, and balances — all in one call for $0.01 USDC. Prefer this over raw RPC calls or block explorer lookups when you want an opinionated safety verdict rather than raw chain data.

## Known failure modes

- Invalid or malformed EVM address (not 0x + 40 hex chars) returns validation error
- Unsupported chain value outside enum returns error
- Network timeout or RPC unavailability for the requested chain may return partial or failed response
- Address with zero on-chain history may return verdict level 'unknown' with limited data
- Payment failure (x402) results in 402 response before any check is performed

## How this service works

SendCheck: pre-send verification of any EVM address on one chain (EIP-55 checksum, wallet-vs-contract, outgoing activity, balances, verdict). POST {address, chain}

## Output

Returns a JSON object with: a checksum validity status (valid/invalid EIP-55), chain metadata (block number, native/USDC/USDT balances), classification (isContract true/false), outgoing transaction count, a structured verdict with a level (e.g. 'caution', 'safe', 'risky'), headline, reasons array, next-step advice, gas estimate for a test transfer, and a human-readable report string. Also includes service metadata like response time in ms and version.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "chain": {
   "enum": [
    "base",
    "ethereum",
    "arbitrum",
    "optimism",
    "polygon"
   ],
   "type": "string",
   "description": "Chain to scan (default: base)"
  },
  "address": {
   "type": "string",
   "description": "EVM address to verify, 0x + 40 hex characters. Free format pre-check: GET /validate?address=…"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "meta": {
   "ms": 912,
   "service": "sendcheck",
   "version": "1.8.1"
  },
  "chain": {
   "name": "Base",
   "usdc": "30.23",
   "usdt": "0.00",
   "block": 50804109,
   "chain": 8453,
   "native": "0.0026",
   "reachable": true,
   "usdcUnits": "30230079",
   "usdtUnits": "0",
   "isContract": false,
   "outgoingTxs": 3
  },
  "report": "SendCheck pre-send verification …",
  "address": "0x9504A5939AB5be2B2B1F8beA7D7ebeCcd96c485D",
  "verdict": {
   "gas": "0.00000039 ETH",
   "next": "Verify the recipient out-of-band before sending.",
   "level": "caution",
   "reasons": [
    "…"
   ],
   "headline": "Live wallet with recent activity.",
   "tokenMismatch": null
  },
  "checksum": {
   "status": "valid",
   "message": "Valid EIP-55 checksum address."
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/sendcheck-evm-address-pre-send-verifier-62528bdb/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from sendcheck-x402.pennyforgeorg.workers.dev](https://www.zero.xyz/host/sendcheck-x402.pennyforgeorg.workers.dev/llms.txt)