NFT metadata endpoint on Base, pay-per-call via x402 with USDC (~$0.02/request).
What it does
This endpoint at lowpaymentfee.com serves NFT metadata for token ID 48 via a POST request, gated by the x402 payment protocol. Each call costs up to 20,000 base units of USDC on the Base network, which translates to $0.02 (USD Coin uses 6 decimals). No API keys or accounts are required — callers simply attach an X-PAYMENT header with a valid x402 payment proof.
The provider, lowpaymentfee.com, 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, generation). All endpoints appear to share the same $0.02/request pricing and x402 payment model on Base. This specific endpoint (`/api/v1/nfts/48/metadata`) returns application/json content, presumably containing on-chain NFT metadata fields such as name, description, image URI, and attributes.
The endpoint is live and returned a proper 402 challenge when probed. However, there is no OpenAPI schema, no documentation beyond the landing page listing, and no example request/response payloads available. The actual structure of the returned NFT metadata is unknown.
Capabilities
Use cases
- —Fetching NFT metadata (name, image, attributes) for token ID 48 programmatically
- —Integrating NFT display data into wallets, marketplaces, or galleries
- —Agent-driven NFT data retrieval without API key management
Fit
Best for
- —Developers needing quick, keyless access to specific NFT metadata
- —AI agents that can settle micropayments via x402 on Base
- —Prototyping NFT-aware applications without signing up for an API provider
Not for
- —Bulk retrieval of metadata across many NFT collections (only one token ID served here)
- —Users who need free or subscription-based NFT metadata APIs
- —Production systems requiring documented schemas and SLAs
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/nfts/48/metadata \
-H "X-PAYMENT: <x402_payment_proof>" \
-H "Content-Type: application/json"Endpoint
Quality
The endpoint is live and returns a valid x402 402 challenge, confirming it is operational. However, there is no OpenAPI schema, no documentation of request/response formats, no example payloads, and the endpoint serves metadata for only a single hardcoded token ID (48). The broader site lists many endpoints but provides no detailed docs for any of them.
Warnings
- —No OpenAPI or schema documentation available for this endpoint
- —No example request or response payloads; actual metadata structure is unknown
- —Endpoint is scoped to a single NFT token ID (48); unclear if other token IDs are available
- —The broader lowpaymentfee.com site pages (/api, /pricing, /README) returned only 'Connect wallet' with no useful content
Citations
- —The endpoint returns a 402 challenge with maxAmountRequired of 20,000 base units of USDC on Base networkhttps://lowpaymentfee.com/api/v1/nfts/48/metadata
- —USDC asset address is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/nfts/48/metadata
- —All listed APIs cost $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com