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 19 via a pay-per-request x402 protocol on the Base network. The caller sends a POST request with an X-PAYMENT header containing a USDC payment proof, and receives JSON metadata in return. The price is 20,000 base units of USDC (6 decimals), which equals $0.02 per request.
The endpoint is part of a broader API platform at lowpaymentfee.com that offers dozens of endpoints across data & analytics, AI & machine learning, finance & Web3, and infrastructure categories — all priced at $0.02 per call. The platform advertises no API keys, no rate limits, and instant access; payment is handled entirely through the x402 protocol settling in USDC on Base.
The specific resource at `/api/v1/nfts/19/metadata` returns NFT metadata in `application/json` format. No OpenAPI schema or detailed documentation for the response body was found, so the exact fields returned are unknown. The x402 challenge confirms the endpoint is live, accepts USDC on Base (contract 0x8335…2913), and pays out to address 0x1A2B…85F3 with a maximum timeout of 300 seconds.
Capabilities
Use cases
- —Fetching metadata for a specific NFT (token 19) programmatically
- —Integrating NFT display data into a dApp or marketplace UI
- —Demonstrating x402 pay-per-call patterns for NFT data retrieval
Fit
Best for
- —Agents or apps needing NFT metadata without API key management
- —Developers exploring x402 micropayment-gated APIs
- —Low-volume, on-demand NFT metadata lookups
Not for
- —Bulk retrieval of metadata across many NFT collections (only token 19 is exposed at this path)
- —Users who need free or subscription-based NFT metadata access
- —Querying metadata for NFTs on networks other than Base
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/nfts/19/metadata \
-H "X-PAYMENT: <x402-payment-proof>" \
-H "Content-Type: application/json"Endpoint
Quality
The x402 challenge is live and confirms pricing, network, and asset details. However, there is no OpenAPI spec, no response schema, no example responses, and the crawled docs pages returned only 'Connect wallet' with no substantive content. The actual metadata payload structure is unknown.
Warnings
- —No OpenAPI or response schema available — the structure of the returned NFT metadata is unknown.
- —Only token ID 19 is exposed at this specific path; it is unclear whether other token IDs are available at similar paths.
- —Documentation pages (/api, /pricing, /README) returned no useful content beyond 'Connect wallet'.
- —The broader platform lists many endpoint categories (AI, finance, etc.) but none were probed; only this single NFT metadata endpoint was verified live.
Citations
- —The endpoint returns HTTP 402 with an x402 challenge advertising USDC on Base at 20,000 base units ($0.02).https://lowpaymentfee.com/api/v1/nfts/19/metadata
- —The platform advertises $0.02/request pricing with no API keys, no rate limits, and instant access.https://lowpaymentfee.com
- —USDC asset contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913.https://lowpaymentfee.com/api/v1/nfts/19/metadata