x402-gated card-transactions 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/96/transactions` behind the x402 payment protocol. When called without payment, it returns a 402 challenge requiring a USDC payment on the Base network. The maximum amount required per call is 20,000 base units of USDC (0.02 USD), settled to address `0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3` using the USDC contract on Base (`0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913`).
The provider's landing page advertises a broad suite of APIs spanning data & analytics, AI/ML inference, finance/Web3, and infrastructure utilities — all priced at $0.02 per request with no API keys, no rate limits, and instant access via the Base network. However, the specific endpoint in this listing (`/api/v1/cards/96/transactions`) is not explicitly listed among those categories on the homepage. Its description in the x402 challenge is simply "Premium API Access," and no further documentation, request schema, or response schema is available. The docs, API, pricing, and README pages all render only a "Connect wallet" prompt with no additional content.
Without documentation or examples, the exact purpose of this card-transactions endpoint is unclear. The path suggests it may relate to retrieving or creating transactions for a specific card (ID 96), but this is speculative. The endpoint accepts POST requests. Pricing is confirmed at $0.02 USDC per call on Base.
Capabilities
Use cases
- —Submitting or retrieving card transaction data via a pay-per-call model
- —Integrating x402-compatible payment flows into agent workflows
- —Accessing premium API resources without API keys using on-chain USDC payments
Fit
Best for
- —Developers building x402-compatible agents that need card transaction endpoints
- —Users who want keyless, pay-per-call API access settled in USDC on Base
- —Prototyping x402 payment integrations with low per-call costs
Not for
- —Users needing detailed API documentation or response schemas before integrating
- —High-volume use cases where $0.02/request adds up without bulk discounts
- —Anyone requiring non-crypto payment methods
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/cards/96/transactions \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-header>" \
-d '{}'Endpoint
Quality
The endpoint is live and returns a valid x402 challenge, confirming pricing and network details. However, there is no documentation, no request/response schema, no examples, and the specific endpoint's purpose is unclear. The docs pages are empty beyond a wallet-connect prompt.
Warnings
- —No documentation available — docs, API, pricing, and README pages all show only 'Connect wallet'
- —The specific endpoint /api/v1/cards/96/transactions is not listed among the provider's advertised APIs on the homepage
- —No request or response schema is provided; the endpoint's exact functionality is unknown
- —The path includes a hardcoded card ID (96), suggesting this may be a resource-specific endpoint rather than a general-purpose API
Citations
- —The x402 challenge requires a maximum of 20,000 base units of USDC (0.02 USD) on the Base networkhttps://lowpaymentfee.com/api/v1/cards/96/transactions
- —The provider advertises $0.02/request pricing with no API keys, no rate limits, and instant access on Basehttps://lowpaymentfee.com
- —USDC contract address on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/cards/96/transactions
- —Docs, API, pricing, and README pages render only a 'Connect wallet' prompthttps://lowpaymentfee.com/docs