Pay-per-call premium API access on Base via x402 — $0.02 per request in USDC.
What it does
This endpoint at lowpaymentfee.com provides "Premium API Access" via the x402 payment protocol. It is one of many endpoints offered by the platform, which spans categories including Data & Analytics, AI & Machine Learning, Finance & Web3, and Infrastructure utilities. All endpoints on the platform are priced at $0.02 per request, payable in USDC on the Base network with no API keys, rate limits, or commitments required.
The specific endpoint `/api/v1/payments/281` returns a valid x402 challenge (HTTP 402) requesting payment of up to 20,000 base units of USDC (0.02 USD, since USDC uses 6 decimals) to wallet `0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3` on Base. The payment scheme is "exact" with a 300-second timeout. The endpoint accepts POST requests and returns `application/json`.
However, the specific functionality behind this particular endpoint (`/api/v1/payments/281`) is not documented beyond the generic label "Premium API Access." The platform's landing page lists numerous other endpoints (metrics, reports, sentiment analysis, summarization, classification, embeddings, price feeds, exchange rates, geocoding, etc.) but does not describe this specific payments path. Documentation pages (`/docs`, `/pricing`, `/README`) returned only a "Connect wallet" prompt with no substantive content. Without further documentation, it is unclear what data or service this endpoint returns once payment is made.
Capabilities
Use cases
- —Programmatic access to a paid API endpoint without needing API keys or subscriptions
- —Agent-driven workflows that settle per-call payments in USDC on Base
- —Testing x402 payment protocol integrations with a low-cost endpoint
Fit
Best for
- —Developers exploring x402 payment protocol integrations
- —AI agents that need keyless, pay-per-use API access
- —Users who prefer crypto micropayments over traditional API billing
Not for
- —Users who need detailed documentation or guaranteed SLAs before paying
- —Anyone without a Base-compatible USDC wallet
- —Use cases requiring free or high-volume bulk pricing
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/payments/281 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is live and returns a valid x402 challenge, but the specific functionality behind /api/v1/payments/281 is undocumented. All documentation pages returned only 'Connect wallet' with no content. No OpenAPI schema, no request/response examples, and no description of what data is returned after payment. The platform lists many other endpoints but this specific one is opaque.
Warnings
- —The specific functionality of /api/v1/payments/281 is not documented — 'Premium API Access' is a generic label with no details on what data or service is returned.
- —All documentation pages (/docs, /pricing, /README) returned only a 'Connect wallet' prompt with no substantive content.
- —No OpenAPI spec, request schema, or response examples are available.
- —This endpoint path (/api/v1/payments/281) does not appear in the platform's listed API catalog, making its purpose unclear.
Citations
- —Platform offers endpoints at $0.02 per request with no API keys, rate limits, or commitmentshttps://lowpaymentfee.com
- —x402 challenge requests maxAmountRequired of 20000 base units of USDC (0.02 USD) on Base networkhttps://lowpaymentfee.com/api/v1/payments/281
- —Payment is to wallet 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3 with 300-second timeouthttps://lowpaymentfee.com/api/v1/payments/281
- —USDC asset address 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/payments/281
- —Platform lists categories: Data & Analytics, AI & Machine Learning, Finance & Web3, Infrastructurehttps://lowpaymentfee.com