x402basequality 0.35

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 (token ID 99) 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 or rate limits are required — callers simply attach an X-PAYMENT header with a valid x402 payment proof.

The provider hosts a broader suite of APIs spanning data & analytics, AI/ML inference (sentiment analysis, summarization, classification, embeddings), finance & Web3 (price feeds, exchange rates, token quotes, gas estimates), and infrastructure utilities (geocoding, validation, conversion, generation). All endpoints are listed at $0.02 per request on the same x402 payment model using USDC on Base. This specific endpoint (/api/v1/nfts/99/owner) is part of the Web3/NFT category, though it is not explicitly listed on the provider's landing page among the featured APIs.

The endpoint is live and returns a proper 402 challenge. However, there is no OpenAPI schema, no documentation beyond the landing page, and no example request/response payloads available. The actual response format for the NFT owner query is unknown — it likely returns JSON with owner address information, but this is inferred, not documented.

Capabilities

nft-ownership-queryx402-micropaymentusdc-paymentbase-networkpay-per-callno-api-keypost-endpoint

Use cases

  • Look up the current owner of a specific NFT programmatically
  • Integrate NFT ownership verification into agent workflows without API key management
  • Pay-per-call NFT data retrieval settled on Base L2

Fit

Best for

  • Agents needing on-demand NFT ownership data without subscription commitments
  • Developers prototyping Web3 apps who want instant API access with no signup
  • Micropayment-based workflows where per-call billing is preferred

Not for

  • Bulk NFT ownership queries across many token IDs (only token 99 is addressed by this endpoint)
  • Users who need free or subscription-based NFT data APIs
  • Production systems requiring documented response schemas and SLAs

Quick start

curl -X POST https://lowpaymentfee.com/api/v1/nfts/99/owner \
  -H "X-PAYMENT: <x402-payment-proof>" \
  -H "Content-Type: application/json"

Endpoint

Transporthttp
Protocolx402
Pay to0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3
CurrencyUSD COIN

Quality

0.35/ 1.00

The endpoint is live and returns a valid x402 402 challenge with clear pricing. However, there is no OpenAPI schema, no documented request/response format, no examples, and the specific NFT endpoint is not even listed on the provider's own landing page. The actual behavior of the endpoint is entirely inferred.

Warnings

  • No OpenAPI or schema documentation available for this endpoint
  • The /api/v1/nfts/99/owner path is not listed among the provider's advertised APIs on the landing page
  • Response format is unknown — no example responses are available
  • The endpoint is hardcoded to token ID 99; it is unclear if other token IDs are supported via similar paths

Citations

Provenance

Indexed fromx402_bazaar
Enriched2026-04-22 00:32:34Z · anthropic/claude-opus-4.6 · v2
First seen2026-04-21
Last seen2026-04-22

Agent access