x402-gated Stripe invoice endpoint on Base, paid per-call in USDC.
What it does
This endpoint at lowpaymentfee.com exposes a Stripe invoice resource (`/api/v1/stripe/invoices/7`) behind an x402 paywall. When called without payment, it returns a 402 challenge requesting USDC on the Base network. The specific endpoint appears to be one of many API routes offered by the lowpaymentfee.com platform, which advertises a broad catalog spanning data analytics, AI/ML inference, finance/Web3 data, and utility services — all gated via x402 at $0.02 per request.
The x402 challenge for this particular endpoint specifies a `maxAmountRequired` of 20,000 base units of USDC (contract `0x8335…2913` on Base). Since USDC uses 6 decimals, this translates to $0.02 per call, consistent with the site's advertised flat pricing. Payment is made via the x402 "exact" scheme to the payTo address `0x1A2B…85F3`, with a 300-second timeout. The endpoint accepts POST requests and returns `application/json`.
Documentation is extremely sparse. The crawled /docs, /api, /pricing, and /README pages all rendered only a "Connect wallet" prompt with no substantive content. There is no OpenAPI spec, no request/response schema, and no explanation of what data the `/stripe/invoices/7` endpoint actually returns. The site's landing page lists many endpoints but provides no detail on inputs or outputs for any of them. Without documentation, it is unclear what request body (if any) this endpoint expects or what the response payload looks like.
Capabilities
Use cases
- —Retrieving Stripe invoice data via a pay-per-call model without API key management
- —Programmatic access to invoice information settled in USDC on Base
- —Agent-driven financial data retrieval with x402 payment gating
Fit
Best for
- —Developers wanting keyless, pay-per-use API access
- —Agents that can settle x402 payments in USDC on Base
- —Use cases requiring on-demand invoice data without subscription commitments
Not for
- —Users needing detailed API documentation or request/response schemas before integrating
- —High-volume consumers who would benefit from bulk pricing or rate-limited plans
- —Anyone without a Base-compatible USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/stripe/invoices/7 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"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 spec, no documentation, no request/response schema, and no examples. The crawled docs/pricing/README pages are all empty beyond a wallet-connect prompt. The specific purpose of '/stripe/invoices/7' is unclear.
Warnings
- —No API documentation available — /docs, /api, /pricing, and /README pages all render only a 'Connect wallet' prompt with no content.
- —No OpenAPI or schema definition found for any endpoint.
- —Request body format and response payload structure are completely unknown.
- —The endpoint path references a hardcoded invoice ID (7), suggesting it may be a demo or single-resource endpoint rather than a general-purpose API.
Citations
- —The x402 challenge specifies maxAmountRequired of 20000 base units of USDC (asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Base network with a 300-second timeout.https://lowpaymentfee.com/api/v1/stripe/invoices/7
- —The site advertises $0.02 per request flat pricing with no API keys, no rate limits, and instant access on Base network.https://lowpaymentfee.com
- —The platform lists endpoints across Data & Analytics, AI & Machine Learning, Finance & Web3, and Infrastructure categories.https://lowpaymentfee.com