x402-gated Stripe invoice endpoint on Base, paying $0.02 in USDC per request.
What it does
This endpoint at lowpaymentfee.com exposes a Stripe invoice resource (`/api/v1/stripe/invoices/170`) behind an x402 payment wall. It is part of a broader platform that offers dozens of pay-per-call APIs spanning data analytics, AI/ML inference, finance/Web3 data, and utility services — all priced at $0.02 per request and settled in USDC on the Base network.
The specific endpoint listed here returns a Stripe invoice (ID 170) as JSON. Payment is handled via the x402 protocol: callers receive a 402 challenge specifying the USDC asset on Base (`0x8335…2913`), a maximum amount of 20,000 base units (i.e., $0.02 given USDC's 6 decimals), and a 300-second timeout. No API keys or rate limits are advertised; access is granted purely through on-chain micropayment.
Documentation on the site is extremely thin — the docs, API, pricing, and README pages all render only a "Connect wallet" prompt with no further content. There is no OpenAPI schema, no request/response examples, and no description of what fields the invoice object contains or what POST body (if any) is expected. The platform appears to be a demonstration or early-stage deployment of x402-gated APIs rather than a mature production service.
Capabilities
Use cases
- —Retrieving Stripe invoice data via a single micropayment without needing an API key
- —Demonstrating x402 protocol integration for pay-per-call APIs
- —Programmatic invoice lookup settled in USDC on Base
Fit
Best for
- —Developers experimenting with x402 payment protocol
- —Agents that can settle USDC micropayments on Base
- —Use cases requiring keyless, per-request API access
Not for
- —Production billing workflows requiring documented, stable Stripe integrations
- —Users who need detailed API documentation or OpenAPI specs before integrating
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/stripe/invoices/170 \
-H "X-PAYMENT: <x402_payment_token>" \
-H "Content-Type: application/json"Endpoint
Quality
The endpoint is live (402 challenge captured) and pricing is clear ($0.02 USDC on Base), but there is no OpenAPI schema, no request/response examples, and all documentation pages render only a wallet-connect prompt. The specific resource (Stripe invoice 170) is opaque with no field descriptions or usage guidance.
Warnings
- —No API documentation available — docs, pricing, and README pages all show only 'Connect wallet'
- —No OpenAPI or JSON schema describing request body or response fields
- —The endpoint targets a specific invoice ID (170); unclear if this is parameterized or a fixed demo resource
- —Platform appears to be early-stage or a demo; reliability and longevity are unknown
Citations
- —The endpoint returns a 402 challenge with maxAmountRequired of 20000 base units in USDC on Basehttps://lowpaymentfee.com/api/v1/stripe/invoices/170
- —All APIs on the platform are priced at $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —USDC asset address on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/stripe/invoices/170