NFT metadata endpoint on Base, pay-per-call via x402 with USDC at $0.02/request.
What it does
This endpoint serves NFT metadata for token ID 51 via a POST request, gated behind an x402 payment challenge. It is hosted on lowpaymentfee.com, a platform offering a broad catalog of pay-per-request APIs spanning data analytics, AI/ML inference, finance/Web3, and infrastructure utilities — all priced uniformly at $0.02 per call.
Payment is settled on the Base network using USDC (contract 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913). The x402 challenge specifies a maxAmountRequired of 20,000 base units, which equals $0.02 (USDC uses 6 decimals). The scheme is "exact", meaning the caller pays the precise amount per request. No API keys or rate limits are advertised; access is granted purely through the x402 payment header.
The specific endpoint `/api/v1/nfts/51/metadata` returns JSON (mimeType: application/json). The broader lowpaymentfee.com platform lists many other endpoints across categories like sentiment analysis, text summarization, geocoding, price feeds, and more, all following the same x402 payment model at the same price point. Documentation beyond the landing page is sparse — the /api, /pricing, and /README pages all resolve to a "Connect wallet" prompt with no additional technical detail.
Capabilities
Use cases
- —Retrieving on-chain NFT metadata for display in wallets or marketplaces
- —Agent-driven NFT data lookups without API key management
- —Programmatic access to NFT attributes for indexing or analytics
Fit
Best for
- —Agents or apps needing NFT metadata with zero signup friction
- —Developers who prefer crypto-native pay-per-call billing on Base
- —Low-volume or sporadic NFT metadata queries where subscriptions are overkill
Not for
- —Bulk NFT metadata ingestion across thousands of tokens (no batch endpoint documented)
- —Users without a Base-network USDC wallet or x402-compatible client
- —Anyone needing detailed API documentation or OpenAPI specs (none provided)
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/nfts/51/metadata \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-header>"Endpoint
Quality
The endpoint is live (402 challenge captured) and pricing is clear ($0.02 USDC on Base). However, there is no OpenAPI schema, no request/response examples, and no documentation beyond a landing page listing. The specific NFT metadata content and expected input/output shapes are entirely unknown.
Warnings
- —No OpenAPI or schema documentation available for this endpoint.
- —No request body or response body examples are documented anywhere.
- —The /api, /pricing, and /README pages all return only a 'Connect wallet' prompt with no useful content.
- —The endpoint is for a specific NFT token ID (51); it is unclear whether other token IDs are available at similar paths.
- —The broader lowpaymentfee.com platform lists many endpoints but provides no technical docs for any of them.
Citations
- —The x402 challenge specifies maxAmountRequired of 20000 base units in USDC on Base networkhttps://lowpaymentfee.com/api/v1/nfts/51/metadata
- —All APIs on the platform are priced at $0.02 per request with no API keys, no rate limitshttps://lowpaymentfee.com
- —USDC asset contract is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/nfts/51/metadata