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 40 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 hosts a broader suite of pay-per-call APIs across categories including data analytics, AI/ML inference (sentiment analysis, summarization, classification, embeddings), finance/Web3 (price feeds, exchange rates, gas estimates), and infrastructure utilities (geocoding, validation, conversion). All endpoints share the same $0.02/request pricing model, no rate limits, and no minimum commitments. Settlement occurs on the Base L2 network using USDC (contract 0x8335…2913).
This specific endpoint returns NFT metadata in application/json format. The exact schema of the returned metadata is not documented, so callers should expect standard NFT metadata fields (name, description, image, attributes) but should verify against actual responses. The x402 challenge confirms the endpoint is live and accepting payments with a 300-second timeout window.
Capabilities
Use cases
- —Fetching NFT metadata for token ID 40 programmatically
- —Integrating pay-per-call NFT data into agent workflows
- —Accessing NFT attributes without managing API keys or subscriptions
Fit
Best for
- —Agents needing on-demand NFT metadata without account setup
- —Developers testing x402 payment flows on Base
- —Low-volume NFT metadata lookups where per-call pricing is economical
Not for
- —Bulk NFT metadata retrieval across many token IDs (only token 40 is at this path)
- —Users who need free or subscription-based access
- —Applications requiring metadata for NFTs on chains other than Base
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/nfts/40/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 schema, no documented request body or response format, no examples, and the endpoint is for a single hardcoded token ID (40) with no explanation of what NFT collection it belongs to. The broader site lists many endpoints but provides no detailed documentation for any of them.
Warnings
- —No response schema or example response documented — actual metadata structure is unknown
- —Endpoint is scoped to a single token ID (40); unclear if other IDs are available at different paths
- —No OpenAPI spec, no README content, and /pricing and /api pages are empty (just 'Connect wallet')
- —The provider lists many API categories (AI, finance, analytics) but none have documented schemas — treat all with caution
Citations
- —Endpoint returns 402 with x402 challenge requiring USDC payment on Base networkhttps://lowpaymentfee.com/api/v1/nfts/40/metadata
- —maxAmountRequired is 20000 base units of USDC (0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) which equals $0.02https://lowpaymentfee.com/api/v1/nfts/40/metadata
- —All endpoints priced at $0.02/request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —Provider offers APIs across data/analytics, AI/ML, finance/Web3, and infrastructure categorieshttps://lowpaymentfee.com