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, paid in USDC on the Base network, with no API keys, rate limits, or commitments required.
The specific endpoint `/api/v1/payments/313` is labeled "Premium API Access" in the x402 challenge but its exact functionality is not documented beyond that label. The x402 challenge confirms it is live, accepts POST requests, and requires a payment of up to 20,000 base units of USDC (0x8335…2913 on Base), which equals $0.02 given USDC's 6 decimals. Payment is sent to address 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3 with a 300-second timeout.
The broader platform advertises endpoints for sentiment analysis, text summarization, classification, embeddings, price feeds, exchange rates, token quotes, gas estimates, geocoding, validation, conversion, and generation — all at the same $0.02 price point. However, documentation pages (/docs, /pricing, /api, /README) all returned only a "Connect wallet" prompt with no substantive content, so the actual request/response schemas for any of these endpoints remain unknown.
Capabilities
Use cases
- —Accessing premium API functionality with per-request USDC micropayments on Base
- —Agent-driven workflows that need keyless, pay-as-you-go API access
- —Testing x402 payment protocol integrations against a live endpoint
Fit
Best for
- —Developers experimenting with x402 payment protocol
- —Agents needing keyless pay-per-call API access on Base
- —Low-volume consumers who want no subscription commitments
Not for
- —Users who need detailed API documentation or guaranteed SLAs
- —High-volume use cases where $0.02/request adds up significantly
- —Anyone without a Base-compatible USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/payments/313 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The x402 challenge is live and confirms pricing and payment details, but the endpoint's actual functionality ("Premium API Access") is completely undocumented. All documentation pages return only a wallet-connect prompt with no content. No request/response schemas, no examples, and no description of what the endpoint actually returns.
Warnings
- —The specific functionality of /api/v1/payments/313 ('Premium API Access') is not documented anywhere in the crawled material.
- —All documentation pages (/docs, /pricing, /api, /README) returned only 'Connect wallet' with no substantive content.
- —No request or response schema is available — callers cannot know what to send or what to expect back.
- —The endpoint path '/api/v1/payments/313' with a numeric ID suggests it may be a dynamic or user-specific resource rather than a general-purpose API.
Citations
- —Endpoint returns 402 with x402 challenge confirming it is livehttps://lowpaymentfee.com/api/v1/payments/313
- —All endpoints priced at $0.02/request with no API keys, no rate limits, instant access on Base networkhttps://lowpaymentfee.com
- —USDC asset address 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/payments/313
- —Platform offers APIs across data & analytics, AI & ML, finance & Web3, and infrastructure categorieshttps://lowpaymentfee.com