Pay-per-call premium API access on Base via x402 protocol at $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. 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/37` is listed under the platform's x402-gated services. The 402 challenge confirms it accepts POST requests, settles in USDC (contract 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Base, and charges a maximum of 20,000 base units (i.e., $0.02 given USDC's 6 decimals). The payment is directed to address 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3 with a 300-second timeout.
Documentation is extremely sparse — the docs, pricing, and API pages all render only a "Connect wallet" prompt with no further technical detail. There is no OpenAPI spec, no request/response schema, and no description of what data or functionality this particular transactions endpoint returns. The platform advertises a broad suite of endpoints but provides minimal information about their actual behavior or output formats.
Capabilities
Use cases
- —Accessing premium data or transaction information without subscription commitments
- —Programmatic pay-per-use API consumption settled in USDC on Base
- —Agent-driven API calls where no API key provisioning is desired
Fit
Best for
- —Developers wanting zero-commitment pay-per-call API access
- —AI agents that can settle payments via x402 protocol on Base
- —Users who prefer crypto-native micropayments over traditional billing
Not for
- —Users needing detailed API documentation or response schemas before integrating
- —High-volume use cases where per-request pricing may be inefficient
- —Users without access to USDC on the Base network
Quick start
# Send a POST with x402 payment header to access the endpoint
curl -X POST https://lowpaymentfee.com/api/v1/transactions/37 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402_payment_token>"Endpoint
Quality
The endpoint is live (402 challenge confirmed) and pricing is clear ($0.02 USDC on Base), but there is no documentation, no request/response schema, and no explanation of what the endpoint actually returns. The docs pages are empty beyond a wallet connect prompt.
Warnings
- —No API documentation available — docs/pricing/API pages only show 'Connect wallet'
- —No OpenAPI spec or response schema provided
- —Purpose of /api/v1/transactions/37 is unclear — 'Premium API Access' is generic
- —Cannot verify what data or functionality this endpoint actually delivers
Citations
- —Platform charges $0.02 per request with no API keys, rate limits, or commitmentshttps://lowpaymentfee.com
- —x402 challenge confirms USDC on Base with maxAmountRequired of 20000 base units ($0.02)https://lowpaymentfee.com/api/v1/transactions/37
- —USDC asset contract is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/transactions/37