x402-gated premium API endpoint on Base, pay-per-call with USDC at $0.02/request.
What it does
This endpoint at `/api/v1/claims/48` is part of the lowpaymentfee.com platform, which offers a collection of x402-protocol pay-per-request APIs spanning data & analytics, AI & machine learning, finance & Web3, and infrastructure utilities. The endpoint is labeled "Premium API Access" and is gated behind an x402 payment challenge requiring USDC on the Base network.
The x402 challenge specifies a maximum amount of 20,000 base units of USDC (asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913, which uses 6 decimals), equating to $0.02 per request. Payment is made via the `exact` scheme to address 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3 with a 300-second timeout. The endpoint accepts POST requests and returns `application/json`.
However, the specific functionality behind `/api/v1/claims/48` is not documented. The site's landing page lists numerous API categories (metrics, reports, sentiment analysis, summarization, classification, embeddings, price feeds, exchange rates, geocoding, validation, conversion, generation) all priced at $0.02/request, but this particular claims endpoint does not appear among them. No OpenAPI schema, request/response examples, or detailed documentation were found — the docs, API, pricing, and README pages all rendered only a "Connect wallet" prompt with no substantive content. The actual input parameters and response format for this endpoint remain unknown.
Capabilities
Use cases
- —Accessing a gated API resource with per-request USDC micropayments on Base
- —Programmatic agent-driven API consumption without API keys or subscriptions
- —Demonstrating x402 protocol payment flows
Fit
Best for
- —Developers experimenting with x402 pay-per-call protocols
- —Agents that can settle USDC payments on Base L2
- —Users who want keyless, commitment-free API access
Not for
- —Users needing well-documented, production-grade APIs with clear schemas
- —Anyone without a Base-compatible USDC wallet
- —Use cases requiring high-volume, low-latency calls where per-request payment overhead matters
Quick start
# 1. Probe the endpoint to get the x402 challenge
curl -X POST https://lowpaymentfee.com/api/v1/claims/48
# Returns 402 with x402 payment challenge in body
# 2. Construct X-PAYMENT header per x402 spec, sign USDC tx on Base
# 3. Replay request with payment header
curl -X POST https://lowpaymentfee.com/api/v1/claims/48 \
-H "X-PAYMENT: <signed-payment-token>"Endpoint
Quality
The endpoint is live (402 challenge confirmed) and pricing is clear ($0.02 USDC on Base), but there is no documentation of what this specific endpoint does, no request/response schema, no examples, and the docs pages are empty. The '/claims/48' path doesn't match any listed API on the site. This is effectively a stub listing.
Warnings
- —The specific functionality of /api/v1/claims/48 is undocumented — it does not appear in the site's listed API catalog
- —All documentation pages (docs, API, pricing, README) returned only 'Connect wallet' with no substantive content
- —No OpenAPI schema, request parameters, or response format available
- —The purpose of the 'claims' resource is unknown — could be a test or internal endpoint
Citations
- —The x402 challenge requires 20000 base units of USDC (asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Base network, equating to $0.02https://lowpaymentfee.com/api/v1/claims/48
- —The site lists APIs across data & analytics, AI & ML, finance & Web3, and infrastructure categories all priced at $0.02/requesthttps://lowpaymentfee.com
- —The site advertises no API keys, no rate limits, instant access, and Base network settlementhttps://lowpaymentfee.com
- —Docs, API, pricing, and README pages render only a 'Connect wallet' prompthttps://lowpaymentfee.com/docs