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 27 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, rate limits, or subscriptions are required — callers simply attach an X-PAYMENT header with a valid x402 payment proof.
The provider's site hosts a broader suite of pay-per-call APIs spanning data analytics, AI/ML inference (sentiment, summarization, classification, embeddings), finance/Web3 (price feeds, exchange rates, gas estimates), and infrastructure utilities (geocoding, validation, conversion). All endpoints appear to share the same $0.02/request pricing and x402 payment model on Base. However, this specific listing covers only the `/api/v1/nfts/27/metadata` endpoint, which returns NFT metadata in JSON format.
The endpoint is live and returns a proper 402 challenge with x402 version 1. The payment asset is USDC (contract 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Base, paid to address 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3. No OpenAPI schema or detailed documentation was found beyond the landing page listing and the 402 challenge itself, so the exact shape of the returned metadata is unknown.
Capabilities
Use cases
- —Retrieving metadata for a specific NFT (token 27) programmatically
- —Integrating NFT display data into wallets or marketplaces
- —Agent-driven NFT data lookups with automatic micropayment settlement
Fit
Best for
- —Developers needing NFT metadata without managing API keys
- —Agents that can settle x402 payments on Base
- —Low-volume, on-demand NFT data retrieval
Not for
- —Bulk retrieval of metadata across many NFT collections (only token 27 is exposed at this path)
- —Users who cannot transact in USDC on Base
- —Applications requiring detailed OpenAPI documentation or guaranteed SLAs
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/nfts/27/metadata \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402_payment_proof>"Endpoint
Quality
The endpoint is live and returns a valid x402 402 challenge with clear pricing. However, there is no OpenAPI schema, no documentation of request/response shapes, and no example payloads. The NFT metadata content is entirely unknown. Score reflects a working but poorly documented endpoint.
Warnings
- —No OpenAPI or schema documentation available — response format is unknown
- —Only a single NFT token ID (27) is exposed at this path; unclear if other token IDs are available at sibling paths
- —No crawled docs beyond a landing page listing; /api, /pricing, and /README pages all returned only a 'Connect wallet' prompt
Citations
- —Endpoint returns HTTP 402 with x402 version 1 challenge, confirming it is livehttps://lowpaymentfee.com/api/v1/nfts/27/metadata
- —maxAmountRequired is 20000 base units of USDC (6 decimals) = $0.02 per requesthttps://lowpaymentfee.com/api/v1/nfts/27/metadata
- —Payment asset is USDC at contract 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Base networkhttps://lowpaymentfee.com/api/v1/nfts/27/metadata
- —Site advertises $0.02/request pricing with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com