NFT metadata endpoint on Base, pay-per-call via x402 with USDC at $0.02/request.
What it does
This endpoint at lowpaymentfee.com serves NFT metadata for token ID 18 via a POST request, gated by the x402 payment protocol. Each call costs $0.02 in USDC on the Base network (maxAmountRequired of 20,000 base units with 6 decimals = $0.02). No API keys or accounts are needed — callers attach an X-PAYMENT header with a valid x402 payment proof and receive JSON metadata in return.
The provider operates a broader platform offering dozens of pay-per-call APIs across categories including data analytics, AI/ML inference, finance/Web3, and infrastructure utilities, all priced uniformly at $0.02 per request. This specific endpoint is part of an NFT-related collection (path: /api/v1/nfts/18/metadata). The x402 challenge confirms the endpoint is live, accepts USDC (contract 0x8335…2913) on Base, and pays out to address 0x1A2B…85F3 with a 300-second payment timeout.
Because the endpoint returns only metadata for a single NFT (token 18), its utility is narrow unless the provider exposes similar endpoints for other token IDs. No OpenAPI schema, request body schema, or example responses were found in the crawl, so the exact structure of the returned metadata is unknown. The platform advertises no rate limits and instant access.
Capabilities
Use cases
- —Retrieving metadata for NFT token 18 from this provider's collection
- —Demonstrating x402 micropayment integration for API access
- —Building NFT display UIs that need on-demand metadata fetching
Fit
Best for
- —Agents or apps needing NFT metadata without managing API keys
- —Developers experimenting with x402 payment-gated endpoints
- —Low-volume, on-demand NFT metadata lookups
Not for
- —Bulk retrieval of metadata across many NFT collections
- —General-purpose NFT indexing (only serves token 18 at this path)
- —Users who need free or subscription-based access
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/nfts/18/metadata \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402_payment_proof>"Endpoint
Quality
The x402 challenge is live and confirms pricing and network details, but there is no OpenAPI schema, no documented request/response format, and no example payloads. The endpoint serves metadata for a single NFT token ID with no broader documentation, making it essentially a stub listing.
Warnings
- —No OpenAPI or request/response schema available — the structure of returned metadata is unknown.
- —Endpoint serves only token ID 18; unclear if other token IDs are available at similar paths.
- —No documentation pages rendered meaningful content (pricing, README, and /api pages only showed 'Connect wallet').
- —Provider platform lists many APIs but none have detailed docs in the crawl.
Citations
- —Endpoint returns HTTP 402 with x402 challenge, confirming it is live on Base with USDChttps://lowpaymentfee.com/api/v1/nfts/18/metadata
- —maxAmountRequired is 20000 base units of USDC (6 decimals) = $0.02 per requesthttps://lowpaymentfee.com/api/v1/nfts/18/metadata
- —Platform advertises $0.02/request, no API keys, no rate limits, instant accesshttps://lowpaymentfee.com
- —USDC asset contract is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/nfts/18/metadata