Pay-per-call premium API access on Base via x402 — $0.02/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 lowpaymentfee.com platform, which hosts a collection of pay-per-request APIs spanning data & analytics, AI & machine learning, finance & Web3, and infrastructure utilities. All endpoints are priced at $0.02 per request, settled in USDC on the Base network, with no API keys, rate limits, or commitments required.
The specific endpoint `/api/v1/payments/355` is labeled "Premium API Access" but its exact functionality is not documented beyond that title. The x402 challenge confirms it is live, accepts POST requests, and charges a maximum of 20,000 base units of USDC (0.02 USD, since USDC uses 6 decimals) per call on the Base network. The payment is sent to address `0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3` and the response MIME type is `application/json`.
The broader platform advertises endpoints for sentiment analysis, text summarization, classification, embeddings, price feeds, exchange rates, geocoding, validation, conversion, and data export — all at the same $0.02 price point. However, documentation pages (`/docs`, `/pricing`, `/api`, `/README`) returned only a "Connect wallet" prompt with no substantive content, so the actual request/response schemas and detailed behavior of this or any other endpoint remain undocumented.
Capabilities
Use cases
- —Accessing premium API functionality with per-request USDC micropayments
- —Integrating pay-as-you-go API calls into agent workflows without API key management
- —Testing x402 payment protocol integrations on Base
Fit
Best for
- —Developers wanting zero-commitment, pay-per-use API access
- —Agent systems that can settle x402 payments in USDC on Base
- —Users who prefer no rate limits and no API key registration
Not for
- —Users who need detailed API documentation or well-defined request/response schemas before integrating
- —Applications requiring non-crypto payment methods
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/payments/355 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is live and returns a valid x402 402 challenge, confirming pricing and network. However, the actual functionality behind "Premium API Access" is entirely undocumented — no request schema, no response schema, no examples, and all documentation pages are empty stubs showing only "Connect wallet". The listing is effectively a stub with confirmed liveness.
Warnings
- —The exact functionality of /api/v1/payments/355 ('Premium API Access') is not documented anywhere in the crawled material.
- —All documentation pages (/docs, /pricing, /api, /README) returned no substantive content — only a 'Connect wallet' prompt.
- —No request or response schema is available; integration requires trial-and-error or out-of-band documentation.
- —The endpoint path '/api/v1/payments/355' with a numeric ID suggests it may be a dynamically generated or ephemeral resource.
Citations
- —Endpoint returns HTTP 402 with x402 challenge, confirming it is live on Base network with USDC paymenthttps://lowpaymentfee.com/api/v1/payments/355
- —maxAmountRequired is 20000 base units of USDC (USD Coin, 6 decimals) = $0.02https://lowpaymentfee.com/api/v1/payments/355
- —Platform advertises $0.02/request pricing with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —Platform offers endpoints across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com
- —Documentation pages returned only 'Connect wallet' with no substantive contenthttps://lowpaymentfee.com/docs