x402-gated Stripe invoice endpoint on Base, pay-per-call with USDC.
What it does
This endpoint at lowpaymentfee.com provides access to a Stripe invoice resource (invoice ID 103) behind an x402 paywall. The endpoint accepts POST requests and returns JSON. Payment is settled on the Base network using USDC (contract 0x8335…2913) via the x402 "exact" scheme. The maximum amount required per call is 20,000 base units of USDC, which equals $0.02 (USDC uses 6 decimals). No API keys or rate limits are advertised; access is granted purely through the x402 payment header.
The hosting site lowpaymentfee.com offers a broader catalog of pay-per-request APIs spanning data analytics, AI/ML inference (sentiment analysis, summarization, classification, embeddings), finance/crypto market data, and utility services — all priced at $0.02 per request. However, this specific listing covers only the `/api/v1/stripe/invoices/103` endpoint. Documentation pages on the site are essentially empty (showing only a "Connect wallet" prompt), so there is no detailed schema, request/response format, or usage guidance available beyond what the x402 challenge itself provides.
The endpoint is confirmed live: the probe received a proper HTTP 402 with a well-formed x402 version 1 challenge. The payTo address is 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3 with a 300-second payment timeout.
Capabilities
Use cases
- —Retrieving Stripe invoice data via a crypto-paywall without traditional API keys
- —Programmatic access to invoice #103 for automated billing or reconciliation workflows
- —Agent-driven payment and data retrieval in a single HTTP round-trip
Fit
Best for
- —Developers wanting keyless, pay-per-use access to invoice data
- —AI agents that can settle x402 payments on Base with USDC
- —Prototyping crypto-gated API access patterns
Not for
- —Users needing bulk invoice retrieval across many invoice IDs
- —Anyone without a Base-compatible USDC wallet
- —Production billing systems requiring detailed API documentation and SLAs
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/stripe/invoices/103 \
-H "X-PAYMENT: <x402-payment-token>" \
-H "Content-Type: application/json"Endpoint
Quality
The endpoint is confirmed live with a valid x402 challenge and clear pricing ($0.02 USDC on Base). However, there is no OpenAPI schema, no request/response examples, and all documentation pages are empty stubs. The purpose of the endpoint ('Premium API Access' for a Stripe invoice) is vague with no detail on what data is returned.
Warnings
- —Documentation pages (/docs, /api, /pricing, /README) are all empty — only a 'Connect wallet' prompt is shown.
- —No request body schema or response schema is documented; callers must guess the expected input/output format.
- —The endpoint path references a specific invoice ID (103); it is unclear whether other invoice IDs are accessible or what data is returned.
- —The description 'Premium API Access' is generic and does not explain the endpoint's actual functionality.
Citations
- —The x402 challenge returns maxAmountRequired of 20000 base units of USDC on Base networkhttps://lowpaymentfee.com/api/v1/stripe/invoices/103
- —USDC asset contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/stripe/invoices/103
- —All APIs on the site are priced at $0.02 per request with no API keys, no rate limitshttps://lowpaymentfee.com
- —The site offers APIs across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com