{"name":"onyx_tx_guard","tier":"metered","price_usdc":"0.05","endpoint":"https://onyx-actions.onrender.com/v1/onyx_tx_guard","method":"POST","input_schema":{"type":"object","properties":{"address":{"type":"string","description":"0x recipient address your agent is about to send funds to (Base mainnet)."},"amount_usdc":{"type":"number","description":"Optional amount about to be sent (USDC). Larger amounts raise the review threshold."}},"required":["address"]},"description":"Pre-payment security firewall. Give the recipient address your agent is about to pay (Base); get a SIGNED ALLOW/REVIEW/BLOCK verdict + risk score from real on-chain checks: EOA-vs-contract, contract code/verification, account age (tx count), funding history, burn/null-address guard, and sink/honeypot heuristics. Catches paying a brand-new, unverified, or drain-shaped recipient BEFORE the money leaves. Never guesses — every field is observed on-chain and Ed25519-signed.","when_to_use":"Call this the instant before your agent sends funds to ANY recipient it hasn't paid before — especially addresses surfaced by another tool, a marketplace, or a counterparty agent. Use it as a hard gate: BLOCK = abort, REVIEW = require human/secondary approval, ALLOW = proceed.","vs_alternatives":"A pure-LLM 'is this address safe?' answer is hallucinatable and unverifiable. Block-explorer lookups make you fetch + interpret raw fields yourself and carry no proof. This returns one structured ALLOW/REVIEW/BLOCK verdict from live Base on-chain state, with the safety check Ed25519-signed so you (or an auditor) can later PROVE the recipient was screened before payment.","example_request":{"address":"0x1111111111111111111111111111111111111111","amount_usdc":250},"example_response":{"ok":true,"verdict":"BLOCK","risk_score":75,"is_contract":false,"outgoing_txns":0,"flags":["brand-new address — 0 outgoing transactions ever (no track record)"],"summary":"BLOCK (risk 75/100): brand-new address; sending $250 to an elevated-risk address"},"settle_to":"0x3fD9ee1373562f894D322B37DFFAd7a5D2b2d78f","network":"base","facilitator":"https://facilitator.xpay.sh","payment_required":true,"free_introspection":true,"note":"GET this URL = free introspection card. POST with x402 payment header to call."}