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 provider, which spans categories including Data & Analytics, AI & Machine Learning, Finance & Web3, and Infrastructure utilities. Each request costs $0.02 in USDC on the Base network, with no API keys, rate limits, or commitments required.
The specific endpoint `/api/v1/transactions/330` accepts POST requests and returns JSON. The x402 challenge confirms it is live, requiring a maximum of 20,000 base units of USDC (0.02 USD, since USDC uses 6 decimals) paid to the specified wallet address. The payment timeout is 300 seconds.
Documentation is extremely sparse — the docs, API, pricing, and README pages all render only a "Connect wallet" prompt with no further technical detail. There is no OpenAPI spec, no request/response schema documentation, and no description of what this particular transactions endpoint actually returns. The provider's landing page lists many endpoints but provides no detail on input parameters or response formats for any of them.
Capabilities
Use cases
- —Accessing premium data or services without subscription commitments
- —Making one-off API calls paid in USDC on Base
- —Agent-driven workflows requiring pay-per-use endpoints
Fit
Best for
- —Developers wanting no-signup, pay-as-you-go API access
- —AI agents with x402-compatible payment capabilities
- —Users who prefer crypto micropayments over traditional billing
Not for
- —Users needing detailed API documentation before integration
- —High-volume use cases where per-request pricing is expensive at scale
- —Developers without USDC on Base network
Quick start
# Send a POST with x402 payment header to access the endpoint
curl -X POST https://lowpaymentfee.com/api/v1/transactions/330 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <your-x402-payment-token>"Endpoint
Quality
The endpoint is confirmed live via a valid 402 challenge, but there is zero documentation on what this specific endpoint does, what inputs it accepts, or what it returns. No OpenAPI spec, no examples, and all doc pages are empty. The listing is effectively a stub.
Warnings
- —No documentation available — all doc/API/pricing/README pages render only 'Connect wallet'
- —No OpenAPI or schema describing request parameters or response format
- —The specific purpose of /api/v1/transactions/330 is unclear — 'Premium API Access' is generic
- —Cannot verify what data or service is actually delivered after payment
Citations
- —Endpoint returns 402 with x402 challenge requiring 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/transactions/330
- —Provider lists multiple API categories at $0.02/request with no API keys, no rate limitshttps://lowpaymentfee.com
- —USDC asset address 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Base networkhttps://lowpaymentfee.com/api/v1/transactions/330