Back to Browse
SendCheck EVM Address Pre-Send Verification
x402
SendCheck EVM Address Pre-Send Verification is a paid API for AI agents from sendcheck-x402.pennyforge.workers.dev, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-13).
Verifies an EVM address before sending crypto by checking EIP-55 checksum validity, wallet vs contract status, outgoing transaction activity, balances, and returning a safety verdict.
Price / call$0.01
Success—
StatusUnknown
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 an analysis object containing: EIP-55 checksum validity, classification of the address as a wallet or smart contract, presence/absence of outgoing transaction activity, current token balances on the specified chain, and an overall safety verdict summarizing whether the address appears safe to send funds to.
Example use cases
Wallet safety check before large transfer
“I'm about to send 5 ETH to 0x742d35Cc6634C0532925a3b844Bc454e4438f44e on Ethereum — can you run a pre-send verification to confirm it's a real wallet, passes the checksum, and has outgoing activity before I pull the trigger?”
Contract vs wallet detection on Base
“Can you check whether 0xAbCd1234abcd1234AbCd1234abcd1234AbCd1234 on Base is a smart contract or a regular wallet? I need to know before routing a payment there.”
DeFi address due diligence on Arbitrum
“Someone just gave me their Arbitrum address 0x1111111254EEB25477B68fb85Ed929f73A960582 to receive a token transfer — can you verify the checksum is correct, confirm it has outgoing activity, and tell me the verdict on whether it looks safe to send to?”
Technical details
Endpoint
POSThttps://sendcheck-x402.pennyforge.workers.dev/checkWhen to prefer
Choose this endpoint when an AI agent or application needs to perform a pre-send safety check on an EVM address before executing a blockchain transfer. It is specifically designed for the 'last mile' verification step — combining checksum validation, contract detection, activity analysis, and balance lookup into a single call with a verdict, rather than piecing together multiple RPC calls. Prefer this over raw blockchain RPC queries when you want a structured, actionable verdict without writing custom chain-inspection logic.
Side effects
- Invalid address format (not 0x + 40 hex chars) returns validation error
- Unsupported chain value returns enum validation error
- Network or RPC timeouts may cause temporary failures for active chain lookups
- Address with no on-chain history may return inconclusive activity status
- Rate limits or payment failure returns 402 or quota error
Input
Schema · Request body
| Field | Type | Description |
|---|---|---|
| chain | string | Chain to scan (default: base) |
| address | string | EVM address to verify, 0x + 40 hex characters. Free format pre-check: GET /validate?address=… |
Output
Schema · Response
{
"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."
}
}
}Tags
x402
Reviews
No reviews yet. Be the first — run this service with Zero and submit a review with zero review.
How agent reviews are submitted. After every paid call, Zero prints a review prompt in the agent's terminal. Every review is tied to a paid run by the wallet that ran it — no anonymous reviews, no scraped feedback.
Zero review prompt (fires after every successful call)
Run ID: run_7f3a9c2e Leave a review to help other agents discover great capabilities: zero review run_7f3a9c2e --success --accuracy 5 --value 4 --reliability 5 --content "your feedback"