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 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/167` is listed as "Premium API Access" but its exact functionality is not documented beyond that label. The x402 challenge confirms it is live, accepts POST requests, and requires 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 platform's documentation pages (docs, pricing, README) all resolve but contain only a "Connect wallet" prompt with no substantive content. As a result, the actual request/response schema for this endpoint is unknown. The broader site lists sibling endpoints for sentiment analysis, text summarization, geocoding, price feeds, and more — all at the same $0.02 price point — but no detailed API documentation is available for any of them.
Capabilities
Use cases
- —Accessing premium API functionality with per-request USDC micropayments on Base
- —Agent-driven API consumption without pre-registration or API keys
- —Programmatic pay-as-you-go access to undocumented premium services
Fit
Best for
- —Developers wanting zero-signup, pay-per-call API access
- —AI agents that can settle x402 payments in USDC on Base
- —Users who prefer crypto micropayments over subscription billing
Not for
- —Anyone needing detailed API documentation or guaranteed SLAs before purchasing
- —Use cases requiring free or fiat-only payment methods
- —Production systems that need well-documented request/response contracts
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/payments/167 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is live and returns a valid x402 challenge, confirming pricing and payment details. However, there is no documentation, no request/response schema, and the actual functionality behind 'Premium API Access' is completely undescribed. All doc pages return only 'Connect wallet' with no content.
Warnings
- —No API documentation available — all doc pages show only 'Connect wallet'
- —The exact functionality of /api/v1/payments/167 ('Premium API Access') is undocumented and unclear
- —No request body schema or response schema is provided
- —The platform lists many endpoints but none have detailed documentation
Citations
- —The endpoint returns a 402 x402 challenge with maxAmountRequired of 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/payments/167
- —All endpoints on the platform are priced at $0.02 per request with no API keys, rate limits, or minimumshttps://lowpaymentfee.com
- —The platform offers endpoints across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com
- —USDC asset address is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Base networkhttps://lowpaymentfee.com/api/v1/payments/167