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 3 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 response.
The provider hosts a broader suite of pay-per-call APIs spanning data analytics, AI/ML inference (sentiment analysis, summarization, classification, embeddings), finance/Web3 data (price feeds, exchange rates, token quotes, gas estimates), and infrastructure utilities (geocoding, validation, conversion, generation). All endpoints share the same $0.02/request pricing model and settle on the Base network using USDC. The platform advertises no rate limits, no minimums, and instant access.
This specific endpoint (/api/v1/nfts/3/metadata) returns NFT metadata in application/json format. The exact schema of the returned metadata is not documented, so the response structure must be discovered by making a paid call. The x402 challenge is live and well-formed, confirming the endpoint is operational.
Capabilities
Use cases
- —Retrieving metadata for a specific NFT (token ID 3) programmatically
- —Integrating NFT display data into wallets or marketplaces without API key management
- —Agent-driven NFT data retrieval with micropayment settlement on Base
Fit
Best for
- —Developers needing on-demand NFT metadata without subscription commitments
- —AI agents that can settle x402 micropayments on Base
- —Applications displaying NFT information that prefer pay-per-use pricing
Not for
- —Bulk retrieval of metadata across many NFT collections (only token ID 3 is exposed at this path)
- —Users who need free or pre-paid API access without crypto wallets
- —Production systems requiring documented response schemas and SLAs
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/nfts/3/metadata \
-H "X-PAYMENT: <x402-payment-proof>" \
-H "Content-Type: application/json"Endpoint
Quality
The x402 challenge is live and well-formed, confirming the endpoint works. However, there is no OpenAPI schema, no documented request/response format, no examples, and the endpoint is narrowly scoped to a single NFT token ID. The broader platform docs are essentially empty beyond a landing page listing endpoints.
Warnings
- —No response schema documented — the structure of the returned NFT metadata is unknown.
- —Endpoint is scoped to a single NFT (token ID 3); unclear if other token IDs are available at similar paths.
- —No OpenAPI spec or detailed API documentation available.
- —The /api, /pricing, and /README pages returned only a 'Connect wallet' prompt with no useful content.
Citations
- —The endpoint returns HTTP 402 with an x402 challenge requiring USDC payment on Base networkhttps://lowpaymentfee.com/api/v1/nfts/3/metadata
- —maxAmountRequired is 20000 base units of USDC (asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913), equaling $0.02https://lowpaymentfee.com/api/v1/nfts/3/metadata
- —The platform advertises $0.02/request pricing with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —The provider offers additional API categories including Data & Analytics, AI & ML, Finance & Web3, and Infrastructurehttps://lowpaymentfee.com