x402 Verification API

Scans untrusted web pages, emails, MCP responses, or A2A payloads for hidden prompt injections and returns sanitized text.

Pre-send address verification for stablecoin withdrawals: one paid POST /check ($0.01) parses address + token contract, probes live RPCs and exchanges, and returns a warn-level verdict before you send USDC. POST /deep ($0.05) adds extended checks.

Machine-to-machine utility APIs for AI agents. 8 endpoints: Python code scanner (security + quality + complexity), email validator (single + bulk), domain intelligence (WHOIS + DNS + SSL + tech stack), PDF to Markdown (standard + large + pre-check), URL to Markdown. All CPU-only, deterministic, zero upstream cost. USDC on Base via x402.

Is this token safe to buy? Honeypot detection, rug-pull and scam check for any ERC-20 token. Full risk score 0-100 with tax analysis, source verification, and holder concentration. GoPlus-powered token security scan. Not an audit.

Signed x402 verification and screening primitives: claim notarization, resolver-graded verdicts, OFAC SDN screening, and validated corporate distress scoring, backed by an on-chain correctness bond.

Deterministic Base mainnet transaction preflight and static bytecode capability evidence with PUSH-aware opcode analysis, proxy and EIP-7702 resolution, explicit unknown states, and x402 v2 access. It does not provide a safety guarantee.

Preserve a public HTTPS page as a full-page browser screenshot, rendered HTML, capture metadata, PDF report and signed integrity receipt. 0.10 USDC per successful capture on Base; downloads available for 30 days. Exact-host loading; no independent timestamp or legal certification.

Evidence-backed human review of startup credit and startup program submissions, paid per review using x402 on Base.

Checksums and fixed reference facts for agents. IBAN, VIN, ISIN, VAT, holidays, time zones, and similar. Unknown input returns 404 and is not charged. No live prices, no live scores, no account or product existence claims.

Paid x402 checks for agents. USDC on Base via OpenX402, no signup. Start free: every door has a /sample (HTTP 200). Geocode $0.01 (/api/v1/geocode?q=, OpenStreetMap Nominatim), Denylist Check $0.01 (/api/v1/denylistcheck?url=), Wallet-can-pay check $0.01 (/api/v1/walletcanpay?url=&wallet=), MCP Tool Price Sheet $0.01 (/api/v1/mcptoolprices?url=), Pipe Check $0.02 (/api/v1/pipecheck?url=), Agent Budget Preflight $0.02 (/api/v1/budgetpreflight?urls=&per_call_cap=&daily_cap=), Sig Class $0.03 (/api/v1/sigclass?reason=), Decscale $0.03 (/api/v1/decscale?url=). Full catalog: paid_sku_count 293 at /.well-known/x402 and /llms.txt. Never invents listed=true or a settle.

Limitguard checks Dutch and Belgian companies, sales leads, sanctions and wallets for AI agents, paid per call in USDC on Base or Solana. x402 agent prices: lead verify $0.05 (KVK/KBO register, VIES VAT, mail server, sanctions, 0-100 lead score), light check $0.05, entity check $0.29, KYB check $0.29, risk score $0.25, entity report $0.55, deep check $0.88, reputation score $0.90, sanctions screen $0.005 (OFAC, EU, UN), agent wallet check $0.005, seller preflight $0.005, wallet balance and compliance alerts $0.11. With the X-Response-Quality: cached header a recent stored answer costs $0.11 for entity check and risk score. Prepaid API keys use the account price list. Current prices are always in https://api.limitguard.ai/.well-known/x402.json.

scvd.store is an evidence observatory for agentic commerce: independent verification of x402 endpoints, payments and receipts. Before an agent pays an x402 endpoint, we check that it can be paid. After it pays, we check the signed receipt. Over time we watch endpoints and publish a dated, signed corpus. Sellers use it to prove a door works; buyers use it before spending. Every artifact is signed, expires, and names what we did not see. Not escrow, not a rating, not a guarantee. Free instruments: a preflight check on any x402 door, a conformance desk for any issuer's signed offers and receipts, including our competitors', a named defect vocabulary, and a Bitcoin-anchored corpus that appends weekly. Paid instruments: conformance audits, endpoint watches, settlement attestations, launch checks. Never a ranking, and never a verdict without its derivation and denominator beside it. Operated by Record Creative Co. LLC.

EU business data for agents: EU VAT number validation via the official VIES service (with flagged national-register fallback when VIES is down), EORI validation via EC EOS, official company-registry lookup, sanctions screening (EU, UN, OFAC SDN, UK), one-call KYB verdict, EN 16931/XRechnung e-invoice validation and a counterparty due-diligence report. Pay per call in USDC on Base: $0.01 per single check, $0.10 per batch, $0.045 per KYB, e-invoice validate $0.03, route $0.02, due-diligence report $0.49. 20 free calls/day per IP without payment. Also a remote MCP server at https://api.wsystem.dev/mcp/. Discovery: /.well-known/x402 and /openapi.json.

Deliverability and authentication report for one real email. Create a test (free), send a message to the address you get, then read the report for $0.05: SPF, DKIM, DMARC, ARC, reverse DNS, blocklist, header and List-Unsubscribe checks. Messages are not stored; rows are deleted after 24 hours.

Skavio LLC pay-per-call native Circle USDC verification on seven blockchains, precise payment matching and evidence PDFs; MCP agent server also available.

A pay-per-download implementation pack for making x402 v2 endpoints discoverable and CI-auditable: OpenAPI x-payment-info, Bazaar discovery metadata, well-known manifest, and automated checks.

Wallet auth for AI agents and developers. Send a wallet and the conditions it must meet (token balance, NFT ownership, EAS attestation, Farcaster and more) and get back a signed yes or no across 37 chains. No API key needed: pay per call in USDC on Base, Polygon, Arbitrum, Solana or Arc. Every result is signed twice, ES256 and a post-quantum ML-DSA-65 signature, and can be checked offline against the published keys. Attest $0.05, trust profile $0.15.

66 deterministic business-identifier validation tools (IBAN, LEI, VAT, SWIFT/BIC, screening + more) paid per call via x402 - gasless USDC on Base. Signed XDR-1 receipts; free tier 3 calls/day; floor $0.005. Non-custodial.

IBAN validation and BIC/SWIFT lookup backed by primary bank registries (GLEIF, SIX, Bundesbank, EBA, Bank of England). Returns bank identity, SEPA and Verification of Payee reachability, sanctions and risk flags, Swiss clearing detail, ISO 20022 structured addresses. Pay per call in USDC via x402, no account needed. MCP server available for AI agents.

Human $1 Stripe checkout and $0.05 Base USDC agent verify over HTTP 402. Self-pay is rejected.

Honeypot and rug-pull safety checker for ERC20 tokens on Base. Analyzes token contracts for common scam patterns and risky functions.

Pay-per-call dependency audit for coding agents. POST a package.json, a requirements.txt, or npm and PyPI package lists and get per-package latest version and publish date, whether a pin is behind, license, deprecation or yanked status, weekly npm downloads, and OSV vulnerabilities with severity and first fixed version. Up to 50 packages per call. $0.01 whole manifest; $0.005 npm-only, PyPI-only, vulns-only. USDC on Base via the Coinbase facilitator, x402 v2, no API keys, no LLM.

Ask which paid API fits your task; get ranked candidates with URL, price, payment network, paid delivery evidence and risk flags where observed. 0.01 USDC on Base or Solana.

Pre-send risk check for AI agents on Base. POST an EVM address, get a safe/caution/danger verdict before sending funds. Signals: OFAC sanctions, scam and exploit lists, live address-poisoning detection (lookalike and fake-token scammers), contract deployer and verification checks, on-chain age/activity, and a permanent reputation graph. Unknown data never returns safe. Tiers quick/standard/deep from $0.02 via x402.