x402-gated Stripe invoice endpoint on Base, pay $0.02 per request in USDC.
What it does
This endpoint at lowpaymentfee.com provides x402-protocol access to a Stripe invoice resource (invoice ID 21). It is part of a broader platform offering pay-per-request APIs across data analytics, AI/ML inference, finance/Web3, and infrastructure utilities — all gated behind x402 payment challenges on the Base network using USDC.
The specific endpoint `/api/v1/stripe/invoices/21` is labeled "Premium API Access" and accepts POST requests. The x402 challenge advertises a maximum cost of 20,000 base units of USDC (0x8335… on Base), which equals $0.02 per request (USDC uses 6 decimals). Payment is sent to address 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3 with a 300-second timeout. The platform advertises no API keys, no rate limits, and instant access.
Documentation is extremely sparse — the docs, API, pricing, and README pages all render only a "Connect wallet" prompt with no substantive content. There is no OpenAPI schema, no request/response examples, and no description of what data the invoice endpoint actually returns. The endpoint is confirmed live (402 challenge captured), but the lack of documentation makes it difficult to know what payload to send or what response to expect.
Capabilities
Use cases
- —Retrieving Stripe invoice data via a pay-per-request model without API key management
- —Programmatic access to invoice records settled in USDC on Base
- —Agent-driven invoice lookups with automatic crypto micropayments
Fit
Best for
- —Developers wanting keyless, pay-as-you-go access to invoice data
- —AI agents that can settle x402 payments on Base
- —Users who prefer crypto micropayments over subscription billing
Not for
- —Anyone needing detailed API documentation or request/response schemas before integrating
- —Bulk invoice processing where per-request fees would accumulate significantly
- —Users without USDC on the Base network
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/stripe/invoices/21 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-header>"Endpoint
Quality
The endpoint is live and returns a valid x402 challenge with clear pricing ($0.02 USDC on Base). However, there is no OpenAPI schema, no documentation beyond a wallet-connect prompt, no request/response examples, and no explanation of what the endpoint actually returns. The listing is effectively a stub.
Warnings
- —No API documentation available — docs, pricing, and README pages all show only 'Connect wallet'
- —No OpenAPI or request/response schema provided
- —Purpose of the specific '/api/v1/stripe/invoices/21' endpoint is unclear beyond the label 'Premium API Access'
- —No examples of expected request body or response format
Citations
- —The x402 challenge advertises maxAmountRequired of 20000 base units of USDC on Base with a 300-second timeouthttps://lowpaymentfee.com/api/v1/stripe/invoices/21
- —Platform advertises $0.02 per request with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —USDC asset address is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Base networkhttps://lowpaymentfee.com/api/v1/stripe/invoices/21