x402-gated card-transactions endpoint on Base, pay $0.02 per request in USDC.
What it does
This endpoint at lowpaymentfee.com exposes a card-transactions resource at `/api/v1/cards/57/transactions` behind the x402 payment protocol. It accepts POST requests and requires a per-call micropayment of $0.02 in USDC on the Base network. The x402 challenge advertises a maxAmountRequired of 20,000 base units of USDC (0x8335…), which at 6 decimals equals $0.02.
The specific endpoint appears to be part of a broader platform that offers multiple API categories including data & analytics, AI & machine learning, finance & Web3, and infrastructure utilities — all priced at $0.02 per request. However, the particular endpoint listed here (`/api/v1/cards/57/transactions`) is not explicitly documented on the provider's landing page among the advertised APIs. Its name "Premium API Access" and the path suggest it returns transaction data for a specific card (ID 57), but no schema, field definitions, or example responses are available.
The platform advertises no API keys, no rate limits, and instant access via the Base network. Documentation pages (/docs, /api, /pricing, /README) all returned only a "Connect wallet" prompt with no substantive content. Without an OpenAPI spec, request/response schemas, or any documentation beyond the landing page summary, the actual behavior and output of this endpoint remain unclear.
Capabilities
Use cases
- —Retrieving transaction records for a specific card via pay-per-call micropayment
- —Integrating card transaction data into agent workflows without API key management
- —Programmatic access to card transaction history settled on Base L2
Fit
Best for
- —Agents needing on-demand card transaction data without subscription commitments
- —Developers experimenting with x402 payment-gated APIs
- —Low-volume, pay-as-you-go transaction lookups
Not for
- —High-volume bulk transaction data retrieval (no documented batch support)
- —Users who need detailed API documentation or guaranteed SLAs before integrating
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/cards/57/transactions \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-header>"Endpoint
Quality
The endpoint is live (402 challenge captured) and pricing is clear ($0.02 USDC on Base). However, this specific endpoint is not listed among the provider's documented APIs, there is no OpenAPI spec, no request/response schema, and all documentation pages are empty beyond a wallet-connect prompt. The actual functionality is inferred solely from the URL path.
Warnings
- —This specific endpoint (/api/v1/cards/57/transactions) is not listed among the provider's advertised APIs on the landing page.
- —No documentation, OpenAPI spec, or response schema is available — all doc pages return only 'Connect wallet'.
- —The endpoint path references a hardcoded card ID (57); it is unclear whether this is a demo or a real resource.
- —Functionality and response format are entirely unknown; use with caution.
Citations
- —The x402 challenge returns maxAmountRequired of 20000 base units of USDC (asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Base network.https://lowpaymentfee.com/api/v1/cards/57/transactions
- —The platform advertises $0.02 per request, no API keys, no rate limits, and instant access on Base network.https://lowpaymentfee.com
- —Documentation pages (/docs, /api, /pricing, /README) returned only a 'Connect wallet' prompt with no substantive content.https://lowpaymentfee.com/docs