x402-gated card-transaction endpoint on Base, pay-per-call with USDC.
What it does
This endpoint at lowpaymentfee.com exposes a card transactions resource at `/api/v1/cards/92/transactions` behind the x402 payment protocol. It accepts HTTP POST requests and requires an X-PAYMENT header carrying a USDC payment on the Base network. The x402 challenge advertises a maximum cost of 20,000 base units of USDC (0x8335…), which at 6 decimals equals $0.02 per request.
The parent site lowpaymentfee.com hosts a broader catalog of pay-per-call APIs spanning data analytics, AI/ML inference, finance/Web3 data, and utility services — all priced at $0.02 per request with no API keys, no rate limits, and no commitments. However, the specific `/api/v1/cards/92/transactions` endpoint is not listed on the site's public catalog, and its exact functionality is undocumented. The path suggests it relates to transaction data for a particular card resource (card ID 92), but no request/response schema, field definitions, or example payloads are available.
The endpoint is live and returns a valid x402 version-1 challenge. Payment settles in USDC on Base to address 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3. No OpenAPI spec, no detailed docs, and no example responses were found during the crawl — the docs, pricing, and API pages all render only a "Connect wallet" prompt with no additional content.
Capabilities
Use cases
- —Retrieving or posting transaction records for a specific card resource
- —Programmatic access to card transaction data without API key management
- —Agent-driven financial data retrieval with per-call USDC micropayments
Fit
Best for
- —Developers wanting keyless, pay-per-call access to card transaction data
- —AI agents that can settle x402 payments in USDC on Base
- —Users who prefer no-subscription, usage-based pricing
Not for
- —Users needing detailed API documentation or guaranteed SLAs before integrating
- —Bulk data exports where per-call pricing would be cost-prohibitive
- —Anyone without a Base-compatible USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/cards/92/transactions \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is live and returns a valid x402 challenge, but there is no documentation, no request/response schema, no examples, and the specific endpoint is not listed on the provider's own catalog. Functionality must be entirely inferred from the URL path. This is effectively a stub listing.
Warnings
- —No API documentation available — docs, pricing, and API pages render only a wallet-connect prompt
- —The /api/v1/cards/92/transactions path is not listed in the provider's public API catalog
- —No request body schema or response schema is provided; callers cannot know what fields to send or expect
- —Endpoint purpose is inferred solely from the URL path; actual behavior is unknown
Citations
- —The x402 challenge advertises maxAmountRequired of 20000 base units of USDC on Base networkhttps://lowpaymentfee.com/api/v1/cards/92/transactions
- —The site advertises $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —USDC contract address 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/cards/92/transactions
- —Docs, pricing, and API pages render only a Connect wallet prompt with no additional contenthttps://lowpaymentfee.com/docs