x402basequality 0.40

Query NFT ownership data via x402 micropayment on Base for $0.02 per request.

Price
0.02 USDC / call
Protocol
x402
Verified
no

What it does

This endpoint at lowpaymentfee.com returns NFT ownership information for a specific NFT (ID 4) via a pay-per-call x402 protocol. The endpoint accepts POST requests and is settled in USDC on the Base network. The x402 challenge advertises a maxAmountRequired of 20,000 base units of USDC (6 decimals), which equals $0.02 per request. No API keys, rate limits, or subscriptions are required — callers simply attach an X-PAYMENT header with a valid x402 payment proof.

The provider, lowpaymentfee.com, hosts a broader suite of x402-gated APIs spanning data analytics, AI/ML inference (sentiment analysis, summarization, classification, embeddings), finance/Web3 data (price feeds, exchange rates, token quotes, gas estimates), and infrastructure utilities (geocoding, validation, conversion, generation). All endpoints are uniformly priced at $0.02 per request and settle on the Base network using USDC.

This specific endpoint (/api/v1/nfts/4/owner) appears to return the current owner of NFT #4. The response MIME type is application/json. No detailed input or output schema documentation was found beyond the x402 challenge metadata, so the exact request body format and response fields are not confirmed.

Capabilities

nft-ownership-lookupx402-micropaymentusdc-settlementbase-networkpay-per-callno-api-keyjson-response

Use cases

  • Querying the current owner of a specific NFT programmatically
  • Integrating NFT ownership checks into agent workflows without API key management
  • Building on-chain data dashboards that verify NFT holders

Fit

Best for

  • Agents needing quick NFT ownership lookups with no signup
  • Developers prototyping x402 payment flows on Base
  • Applications requiring per-call billing without subscriptions

Not for

  • Bulk NFT collection scans across thousands of token IDs
  • Historical ownership or transfer history queries (not indicated by this endpoint)
  • Users who cannot transact in USDC on the Base network

Quick start

curl -X POST https://lowpaymentfee.com/api/v1/nfts/4/owner \
  -H "Content-Type: application/json" \
  -H "X-PAYMENT: <x402_payment_proof>"

Endpoint

Transporthttp
Protocolx402
Pay to0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3
CurrencyUSD COIN

Quality

0.40/ 1.00

The endpoint is live (402 challenge captured) with clear pricing ($0.02 USDC on Base), but there is no OpenAPI schema, no documented request/response format, and no examples. The endpoint path suggests NFT ownership data but specifics are inferred from the URL alone.

Warnings

  • No OpenAPI or detailed schema documentation available for this endpoint.
  • Exact request body format and response fields are unknown — only the x402 challenge metadata was captured.
  • The endpoint is scoped to a single NFT ID (4); it is unclear whether other NFT IDs are supported at different paths.
  • Crawled /api, /pricing, and /README pages returned only 'Connect wallet' with no useful content.

Citations

Provenance

Indexed fromx402_bazaar
Enriched2026-04-22 00:17:30Z · anthropic/claude-opus-4.6 · v2
First seen2026-04-21
Last seen2026-04-22

Agent access