SKAVIO · DEVELOPER DOCUMENTATION

USDC verification API and MCP reference

Verify native Circle USDC across Base, Polygon, Arbitrum, OP Mainnet, Ethereum, Avalanche and Solana. All API purchases settle in USDC on Base through x402 v2.

See service pricing →Download OpenAPI JSON Discovery manifest

01 · PAY AND USE

How it works

Make a GET request. The first response returns HTTP 402 Payment Required and a PAYMENT-REQUIRED header with the exact amount, asset, Base network and receiver. An x402-compatible client signs a payment and retries with the PAYMENT-SIGNATURE header. The facilitator verifies and settles the payment; only then can the protected API return its result.

GET https://www.skavio.eu/x402/v1/usdc/verify?tx_hash=0x...&network=base
→ HTTP 402 · native USDC / eip155:8453 · 0.02 USDC
→ Client submits signed x402 payment
→ Paid GET response: JSON evidence

No wallet private keys are shared with Skavio. Do not send seed phrases. All data endpoints are read-only.

02 · 0.02 USDC

Verify a native USDC transaction

GET /x402/v1/usdc/verify

tx_hash=0x...  (EVM hash) or Solana base58 transaction signature
network=base | polygon | arbitrum | optimism | ethereum | avalanche | solana

Returns blockchain, native token address/mint, confirmation or finalization status, transfer owners, native USDC amounts and transaction timestamp. Pending / not fully confirmed transfers are never reported as finalized.

03 · 0.03 USDC

Match exact recipient and amount

GET /x402/v1/usdc/match

tx_hash=0x... (or Solana base58 signature)
network=polygon
recipient=0x... (for Solana: base58 owner wallet)
amount=12.500000

Returns matched: true only when exactly one finalized native USDC transfer matches the recipient and exact six-decimal amount. Duplicate matching transfers return false to avoid ambiguity.

04 · 0.05 USDC

Download transaction evidence PDF

GET /x402/v1/usdc/evidence.pdf

tx_hash=0x... (or Solana base58 signature)
network=ethereum

Returns a timestamped PDF document of public blockchain evidence. It is not a tax invoice, receipt for a commercial sale or a guarantee of third-party authorization.

MCP · AGENT PAYMENT INTEGRATION

Connect Skavio as a paid MCP server

Use our public Streamable HTTP endpoint in an MCP client: https://www.skavio.eu/mcp. Discovery of all tools and the free skavio_catalog tool require no payment. The server offers these paid tools:

verify_native_usdc(tx_hash, network="base")     0.02 USDC
match_native_usdc_payment(tx_hash, recipient, amount, network="base")   0.03 USDC
usdc_transfer_evidence_pdf(tx_hash, network="base")  0.05 USDC
domain_dns_tls_audit(domain)                   0.05 USDC

Payment protocol: x402 MCP transport v2. An unpaid tool call returns a machine-readable PaymentRequired result, including the native Circle USDC address on eip155:8453. An x402-capable agent prepares its own signed payment, retries with params._meta["x402/payment"], and the server independently verifies, executes and settles the transaction.

General MCP clients can browse the catalog. Paid execution requires an x402-aware MCP client capable of signing payments. The MCP server cannot access a buyer's wallet, and Skavio never requests private keys. A standard x402 HTTPS API is also available above.

MCP server metadata Pricing & tools

05 · DISCOVERY

Documentation for automated agents

OpenAPI 3 JSON Root x402 manifest Health check

Exact merchant prices are in the HTTP 402 payment challenge and never change according to the blockchain being inspected. Payment chain is eip155:8453, not the selected inspection network. Network data is sourced from independent public RPC providers and can be temporarily unavailable.

Production availability

Public USDC verification, matching, PDF evidence and DNS/TLS tools use per-call x402 fees. PayAPI publishes separate historical settlement receipts for HTTP Verify, Match and PDF evidence; each route is linked below. Authenticated processing uses separate company credentials and backend operation availability; no funded processing acceptance or profitability is asserted here.

The HTTP /x402/v1/processing routes are disabled. A wallet-capable x402 extension is required for paid MCP calls.

HTTP availability policy · Authenticated processing catalog

Find Skavio in AI Agent Marketplaces

Skavio USDC Payment Verification — x402 API. Inspect seven blockchains; pay API fees in native Circle USDC on Base. Verify 0.02 USDC, Match 0.03 USDC, PDF evidence 0.05 USDC per call.

Official MCP Registry: paid verification and proof MCP — published remote server; stable name eu.skavio/paid-micro-apis.
PayAPI Market: USDC transaction verification — settlement-verified /verify, 0.02 USDC. Each link below has its own published historical receipt; this is not a new paid test.
PayAPI Market: exact recipient and amount matching — independently settlement-verified /match, 0.03 USDC.
PayAPI Market: blockchain PDF payment evidence — independently settlement-verified /evidence.pdf, 0.05 USDC. Blockchain evidence is not a tax invoice.
x402scan: three HTTP resources — registered; external display metadata may lag the API.
x402 List: USDC verification and paid MCP tools — accepted public service profile with three tracked HTTP endpoints.
Glama: paid MCP connector — public imported listing; scan freshness is controlled by the directory.
GitHub: MCP integration and quickstart · HTTP API documentation.

Separate company integration: Skavio PDF, OCR & Document Processing MCP uses company OAuth and shared credits at https://www.skavio.eu/processing/mcp. These are directory links, not partner endorsements.

Connect an agent and make the first unpaid request

Choose verify_native_usdc to inspect transfers and confirmation status, match_native_usdc_payment for exactly one finalized recipient and amount match, or usdc_transfer_evidence_pdf for blockchain evidence, not a tax invoice. domain_dns_tls_audit checks public DNS and TLS for 0.05 USDC; it is not a vulnerability scan.

A standard MCP client without a wallet x402 extension cannot automatically pay. Adding the server enables discovery; it does not authorize spending. No private key, seed phrase or wallet secret belongs in Skavio requests.

Cursor: remote MCP configuration

Add to your MCP settings or project .cursor/mcp.json. This public connection needs no API key for catalog discovery.

{"mcpServers":{"skavio-usdc":{"url":"https://www.skavio.eu/mcp"}}}

Claude Code

claude mcp add --transport http skavio-usdc https://www.skavio.eu/mcp

Equivalent .mcp.json:

{"mcpServers":{"skavio-usdc":{"type":"http","url":"https://www.skavio.eu/mcp"}}}

Claude Desktop: local bridge configuration

For Desktop versions using local stdio configuration, Node.js and the third-party mcp-remote bridge can connect to the remote server. Review the bridge before running it; npx may download it. This bridge alone does not add wallet payment support. Desktop versions with remote connectors can add the HTTPS URL directly.

{"mcpServers":{"skavio-usdc":{"command":"npx","args":["-y","mcp-remote","https://www.skavio.eu/mcp"]}}}

REST: an unpaid HTTP 402 example

curl -i 'https://www.skavio.eu/x402/v1/usdc/verify?tx_hash=0x98809948204426c574b6f0aabdec03baa996b5c43ce28cc9ca704fa5d07e592e&network=base'

This GET requires no key or transfer and returns HTTP 402 with a base64 PAYMENT-REQUIRED header. It does not execute the paid handler. Decode the header to inspect the price, native Base USDC asset, payee, expiry and Bazaar input/output schemas.

Use an x402 v2 compatible wallet client. Inspect the challenge and approve the exact fee before signing; fees are 20000, 30000 or 50000 atomic USDC for Verify, Match or PDF respectively.
The wallet signs a restricted payment authorization. Retry the same HTTP request using PAYMENT-SIGNATURE. MCP clients retry the same tool and arguments with params._meta["x402/payment"]. Never send a private key.
Inspect the returned payment receipt and result. RPC outages, invalid input and insufficient finality can prevent a useful result. Read error and retry guidance; do not blindly create another authorization after an uncertain response.

Inspection networks: Base, Polygon, Arbitrum, Optimism, Ethereum, Avalanche and Solana. Fees always settle on Base. EVM inspection requires a 0x plus 64-hex transaction hash; Solana requires its base58 signature. Match also requires a recipient wallet and positive decimal USDC string with at most six decimal places. EVM thresholds vary by chain; Solana uses finalized data. Public RPC latency and availability are variable; no fixed latency SLA is promised.

Authenticated processing is separate: OAuth Processing MCP documentation · Agent Tools key and job instructions · current operation availability and prices. AgentTools relay calls require a company key, workload quote or prepaid credits, the same idempotency key on retries, then status polling and result SHA256 verification. The HTTP /x402/v1/processing routes remain disabled; there is no anonymous document execution.

Schemas, examples and errors · Three-route discovery manifest · Pinned published MCP manifest · Agent navigation · Developer pricing.

Client references: Cursor MCP · Claude Code MCP. Client support and configuration vary by version.