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/transfers/149` 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 listed at $0.02 per request.
However, the specific functionality of the `/api/v1/transfers/149` endpoint is unclear. The description is simply "Premium API Access" with no further documentation, input schema, or example responses available. The docs, pricing, and API pages all returned only a "Connect wallet" prompt with no substantive content. Without documentation or example payloads, it is difficult to determine what this particular endpoint actually does or returns.
Capabilities
Use cases
- —Accessing premium API endpoints without traditional API key registration
- —Making one-off API calls paid in USDC on Base
- —Agent-driven workflows that need keyless, pay-as-you-go API access
Fit
Best for
- —Developers who want instant API access without signup or API keys
- —AI agents that can settle x402 payments autonomously
- —Users who prefer crypto micropayments over subscription billing
Not for
- —Users who need detailed API documentation before integrating
- —High-volume callers who would benefit from bulk pricing or subscriptions
- —Anyone without a Base-network USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transfers/149 \
-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 it accepts USDC on Base at $0.02/request. However, there is no documentation, no input/output schema, no example requests or responses, and the endpoint name 'Premium API Access' is entirely generic. The docs pages are empty. It is impossible to determine what this endpoint actually does.
Warnings
- —No documentation available — docs, pricing, and API pages all render only a 'Connect wallet' prompt with no content.
- —The specific functionality of /api/v1/transfers/149 is unknown; 'Premium API Access' is not descriptive.
- —No input or output schema provided; callers cannot know what to send or expect back.
- —The platform lists many API categories but none have visible documentation or examples.
Citations
- —The endpoint returns a 402 challenge with maxAmountRequired of 20000 base units of USDC on Base networkhttps://lowpaymentfee.com/api/v1/transfers/149
- —USDC asset address 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/transfers/149
- —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