Pay-per-call API platform on Base network via x402 — $0.02/request in USDC.
What it does
lowpaymentfee.com is a pay-per-request API platform that uses the x402 protocol to accept USDC payments on the Base network. The specific endpoint `/api/v1/transactions/196` is listed as "Premium API Access" and returns a 402 challenge requiring payment of up to 20,000 base units of USDC (i.e., $0.02) per call. No API keys or rate limits are required; callers simply attach an X-PAYMENT header with a valid x402 payment proof.
The broader platform advertises multiple API categories including Data & Analytics (metrics, reports, data export, insights), AI & Machine Learning (sentiment analysis, text summarization, classification, embeddings), Finance & Web3 (price feeds, exchange rates, token quotes, gas estimates), and Infrastructure utilities (geocoding, validation, conversion, generation). All endpoints are uniformly priced at $0.02 per request.
However, the specific functionality behind `/api/v1/transactions/196` is not documented beyond the label "Premium API Access." The crawled docs, pricing, and README pages all returned only a "Connect wallet" prompt with no additional content. There is no OpenAPI schema, no request/response examples, and no detailed documentation available for this or any other endpoint on the platform. The endpoint is confirmed live (402 challenge captured), but what data or service it actually returns upon successful payment is unknown.
Capabilities
Use cases
- —Accessing premium API data with per-request USDC micropayments on Base
- —Agent-driven workflows that need keyless, pay-as-you-go API access
- —Testing x402 protocol integrations with a low-cost endpoint
Fit
Best for
- —Developers experimenting with x402 payment protocol
- —Agents needing keyless API access with crypto micropayments
- —Low-volume, on-demand API consumption without subscriptions
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-network USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transactions/196 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-proof>"Endpoint
Quality
The endpoint is live and returns a valid x402 402 challenge, confirming pricing and payment details. However, there is no documentation, no OpenAPI schema, no request/response examples, and the actual functionality behind 'Premium API Access' is completely undocumented. The docs, pricing, and README pages are all blank beyond a wallet-connect prompt. This is effectively a stub listing.
Warnings
- —The actual data or service returned by /api/v1/transactions/196 upon successful payment is unknown — 'Premium API Access' is the only description available.
- —No OpenAPI schema, request format, or response examples are documented anywhere on the site.
- —All documentation pages (docs, pricing, README, api) returned only a 'Connect wallet' prompt with no substantive content.
- —The platform lists many endpoint categories (AI, analytics, finance, infrastructure) but none have publicly visible documentation to verify functionality.
Citations
- —Endpoint returns a 402 challenge with maxAmountRequired of 20000 base units of USDC on Base networkhttps://lowpaymentfee.com/api/v1/transactions/196
- —USDC asset address 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/transactions/196
- —Platform advertises $0.02/request pricing with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —Multiple API categories listed: Data & Analytics, AI & ML, Finance & Web3, Infrastructurehttps://lowpaymentfee.com