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 28 via a POST request, gated by the x402 payment protocol. It is hosted on lowpaymentfee.com, a platform that offers a broad catalog of pay-per-request APIs spanning data analytics, AI/ML inference, finance/Web3, and infrastructure utilities — all settled on the Base network using USDC.
The specific endpoint at `/api/v1/nfts/28/metadata` costs $0.02 per request (20,000 base units of USDC with 6 decimals). Payment is made inline via the X-PAYMENT header; no API keys, accounts, or rate limits are required. The x402 challenge confirms the endpoint is live, accepting the "exact" payment scheme on Base mainnet, paying to address 0x1A2B…85F3, with a 300-second payment timeout. The response MIME type is `application/json`.
Beyond this NFT metadata endpoint, the platform advertises additional APIs at similar pricing ($0.02/request) including sentiment analysis, text summarization, classification, embeddings, price feeds, exchange rates, geocoding, and more. However, no OpenAPI schema, request/response examples, or detailed documentation were found for any endpoint. The actual structure of the NFT metadata returned is unknown — the listing is based solely on the x402 challenge and the provider's landing page.
Capabilities
Use cases
- —Fetching on-chain NFT metadata for display in wallets or marketplaces
- —Programmatic retrieval of NFT attributes for indexing or analytics
- —Agent-driven NFT data lookup without pre-registration or API keys
Fit
Best for
- —Agents needing NFT metadata without account setup
- —Low-volume, on-demand NFT data retrieval
- —Developers experimenting with x402 micropayments on Base
Not for
- —Bulk or high-throughput NFT metadata indexing (no documented batch endpoint)
- —Users who need detailed documentation or response schema guarantees before integrating
- —Querying arbitrary NFT token IDs (this endpoint is scoped to token 28)
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/nfts/28/metadata \
-H "X-PAYMENT: <x402_payment_token>" \
-H "Content-Type: application/json"Endpoint
Quality
The endpoint is confirmed live via a valid x402 402 challenge, and pricing is clear ($0.02 USDC on Base). However, there is no OpenAPI schema, no request body documentation, no example responses, and no description of what the NFT metadata actually contains. The endpoint is scoped to a single token ID with no broader context.
Warnings
- —No OpenAPI or schema documentation available for this endpoint
- —Response body structure is completely unknown — no examples or field descriptions found
- —Endpoint is hardcoded to NFT token ID 28; unclear if other token IDs are available at similar paths
- —Landing page lists many APIs but /api, /pricing, and /README pages all returned only 'Connect wallet' with no useful content
Citations
- —Endpoint returns 402 with x402 challenge accepting USDC on Base network at 20,000 base units ($0.02)https://lowpaymentfee.com/api/v1/nfts/28/metadata
- —Platform advertises $0.02/request pricing with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —USDC asset contract on Base: 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/nfts/28/metadata