Transaction Pre-flight Check
GET api.eucompliance.tools/x402/preflight
Why an agent can trust this route.
Sonar evidence is advisory. Paid delivery is shown as verified only when paid probes are available; otherwise route estimates use the unpaid handshake as a clearly labeled proxy.
Observed outcomes
Agent Transaction Guard: should an autonomous agent proceed, review or block this transaction? Five read-only on-chain core checks before gas is spent: native balance and gas price, transaction-specific gas estimate, full simulation with decoded revert reason, pending nonce gap and recipient bytecode/type. Supplying token, amount and an optional spender adds an ERC-20 balance and allowance check. Returns a stable machine-readable decision, evidence, unknowns, limitations and safe next actions. Missing evidence is REVIEW, never a false approval. Read-only; no transaction is broadcast and there are no follow-up charges. Wallet sanctions screening is outside this contract because official name lists cannot clear or identify a blockchain address.
Resource: api.eucompliance.tools/x402/preflight
Network: eip155:8453, eip155:42161, eip155:137, solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp · Asset: 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 · Pay to: 0x478bCdeA94b9CB5EA14C33e6f0d7E920743d39f2
Payment methods: — · Last validation: 2026-09-14 16:30:18.568+00
{
"input": {
"type": "object",
"required": [
"type",
"method"
],
"properties": {
"type": {
"type": "string",
"const": "http"
},
"method": {
"enum": [
"GET",
"HEAD",
"DELETE"
],
"type": "string"
},
"queryParams": {
"type": "object",
"required": [
"sender",
"to"
],
"properties": {
"to": {
"type": "string",
"description": "contract or wallet being called"
},
"data": {
"type": "string",
"description": "calldata hex, default 0x"
},
"chain": {
"enum": [
"base",
"ethereum",
"arbitrum",
"optimism",
"polygon"
],
"type": "string"
},
"token": {
"type": "string",
"description": "optional ERC-20 to check balance/allowance for"
},
"amount": {
"oneOf": [
{
"type": "string"
},
{
"type": "number"
}
],
"description": "exact token amount intended; decimal string preferred"
},
"sender": {
"type": "string",
"description": "the wallet that would send"
},
"spender": {
"type": "string",
"description": "optional spender, defaults to 'to'"
},
"value_eth": {
"oneOf": [
{
"type": "string"
},
{
"type": "number"
}
],
"description": "exact native value to attach; decimal string preferred"
}
}
}
},
"additionalProperties": false
},
"output": null,
"paymentRequirements": [
{
"raw": {
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"extra": {
"name": "USD Coin",
"version": "2"
},
"payTo": "0x478bCdeA94b9CB5EA14C33e6f0d7E920743d39f2",
"amount": "20000",
"scheme": "exact",
"network": "eip155:8453",
"maxTimeoutSeconds": 300
},
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"payTo": "0x478bCdeA94b9CB5EA14C33e6f0d7E920743d39f2",
"scheme": "exact",
"network": "eip155:8453",
"amountAtomic": "20000"
},
{
"raw": {
"asset": "0xaf88d065e77c8cC2239327C5EDb3A432268e5831",
"extra": {
"name": "USD Coin",
"version": "2"
},
"payTo": "0x478bCdeA94b9CB5EA14C33e6f0d7E920743d39f2",
"amount": "20000",
"scheme": "exact",
"network": "eip155:42161",
"maxTimeoutSeconds": 300
},
"asset": "0xaf88d065e77c8cC2239327C5EDb3A432268e5831",
"payTo": "0x478bCdeA94b9CB5EA14C33e6f0d7E920743d39f2",
"scheme": "exact",
"network": "eip155:42161",
"amountAtomic": "20000"
},
{
"raw": {
"asset": "0x3c499c542cEF5E3811e1192ce70d8cC03d5c3359",
"extra": {
"name": "USD Coin",
"version": "2"
},
"payTo": "0x478bCdeA94b9CB5EA14C33e6f0d7E920743d39f2",
"amount": "20000",
"scheme": "exact",
"network": "eip155:137",
"maxTimeoutSeconds": 300
},
"asset": "0x3c499c542cEF5E3811e1192ce70d8cC03d5c3359",
"payTo": "0x478bCdeA94b9CB5EA14C33e6f0d7E920743d39f2",
"scheme": "exact",
"network": "eip155:137",
"amountAtomic": "20000"
},
{
"raw": {
"asset": "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v",
"extra": {
"feePayer": "D6ZhtNQ5nT9ZnTHUbqXZsTx5MH2rPFiBBggX4hY1WePM"
},
"payTo": "9N5TAHbtp9s8Ksrcn4b9Kig4uTRnevZC13bSsMnMAQ4c",
"amount": "20000",
"scheme": "exact",
"network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
"maxTimeoutSeconds": 300
},
"asset": "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v",
"payTo": "9N5TAHbtp9s8Ksrcn4b9Kig4uTRnevZC13bSsMnMAQ4c",
"scheme": "exact",
"network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
"amountAtomic": "20000"
}
]
}Source catalog records are retained separately from live endpoint observations. Sonar score, uptime, and latency are advisory metrics. CDP indexing is not inferred from validation.