Check a Base address before an agent pays or approves it
Check a Base address before an agent pays or approves it. Input: one address. Output: allow or warn. Reports wallet or contract, whether the wallet has sent a transaction, whether a contract already had code 7 days ago, and whether it is a proxy (EIP-1967, EIP-1167, or implementation()). Warns on contract_is_new, proxy, or no_outgoing_transactions. Wallet age is unknown. A deleted contract looks like a wallet. Not proof of theft.
Answeringour last check, 2026-10-10
1 of 1checks answered this week
418 msmedian answer time
$0.01listed price per call
$0.01price it asked us
Paid test badge: not yet. The checks above are free: we call the tool without paying and read the payment request it sends back. The Verified badge needs paid calls whose answers match the promised output, and nobody can buy a badge.
Endpoint
GET https://base-token-check.fly.dev/v1/counterparty-check
| Category | Code and developer |
|---|---|
| Provider host | base-token-check.fly.dev |
| Networks | eip155:8453 |
| Payment schemes | exact |
| Self-reported calls, 30 days | 2 from 1 payers (the provider's figure, not ours) |
Our checks, last 30 days
| Day | Result | HTTP | Asked | Time |
|---|---|---|---|---|
| 2026-10-10 | valid payment request | 402 | $0.01 | 418 ms |
Example input (from the provider)
{
"method": "GET",
"queryParams": {
"address": "0x540c2aA2526C9c8c2fb4632f0fED668C36424Cd5"
},
"type": "http"
}
Promised output schema (from the provider)
{
"$schema": "https://json-schema.org/draft/2020-12/schema",
"properties": {
"input": {
"additionalProperties": false,
"properties": {
"method": {
"enum": [
"GET",
"HEAD",
"DELETE"
],
"type": "string"
},
"queryParams": {
"properties": {
"address": {
"description": "Wallet or contract on Base to check before paying or approving it.",
"pattern": "^0x[0-9a-fA-F]{40}$",
"type": "string"
}
},
"required": [
"address"
],
"type": "object"
},
"type": {
"const": "http",
"type": "string"
}
},
"required": [
"type",
"method"
],
"type": "object"
},
"output": {
"properties": {
"example": {
"type": "object"
},
"type": {
"type": "string"
}
},
"required": [
"type"
],
"type": "object"
}
},
"required": [
"input"
],
"type": "object"
}