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 at `/api/v1/transactions/290` is labeled "Premium API Access" and returns a 402 challenge requesting up to 20,000 base units of USDC (i.e., $0.02) per call. The platform advertises no API keys, no rate limits, and instant access — you simply attach an x402 payment header to each request.
The broader platform offers endpoints across four categories: 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 listed at $0.02 per request.
However, documentation is extremely sparse. The docs, API, pricing, and README pages all render only a "Connect wallet" prompt with no further content. There is no OpenAPI schema, no request/response examples, and no description of what the `/api/v1/transactions/290` endpoint actually returns. The endpoint is live (confirmed via 402 challenge), but without documentation it is unclear what data or functionality it provides.
Capabilities
Use cases
- —Accessing premium data or transaction information via a single paid HTTP call
- —Agent-driven workflows that need keyless, pay-as-you-go API access
- —Testing x402 protocol integrations with low-cost endpoints
Fit
Best for
- —Developers experimenting with x402 payment protocol
- —AI agents that need frictionless, keyless API access
- —Low-volume, pay-per-use API consumption without subscriptions
Not for
- —Production workloads requiring well-documented, schema-validated APIs
- —Users who need free or subscription-based access without per-call crypto payments
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transactions/290 \
-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, there is no OpenAPI schema, no request/response examples, and all documentation pages are empty beyond a wallet-connect prompt. The purpose of the specific /api/v1/transactions/290 endpoint is unknown. This is effectively a stub listing.
Warnings
- —No documentation available — docs, API, pricing, and README pages all show only 'Connect wallet' with no content.
- —No OpenAPI or schema definition for any endpoint.
- —The specific purpose of /api/v1/transactions/290 ('Premium API Access') is undocumented — it is unclear what data it returns.
- —No request or response examples available anywhere in crawled material.
- —The platform lists many endpoint categories (AI, finance, data, infrastructure) but provides zero detail on any of them.
Citations
- —The endpoint returns a 402 challenge requesting up to 20,000 base units of USDC ($0.02) on Base networkhttps://lowpaymentfee.com/api/v1/transactions/290
- —Platform advertises $0.02/request pricing with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —USDC asset contract on Base: 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/transactions/290
- —Platform offers endpoints across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com
- —Docs, API, pricing, and README pages render only 'Connect wallet' with no further contenthttps://lowpaymentfee.com/docs