x402-gated Stripe invoice endpoint on Base, pay-per-call with USDC.
What it does
This endpoint at lowpaymentfee.com provides "Premium API Access" behind an x402 payment wall. The specific resource path (`/api/v1/stripe/invoices/145`) suggests it returns or processes a Stripe invoice record. Payment is settled on the Base network using USDC (contract 0x8335…2913) via the x402 exact-payment scheme. The maximum amount required per call is 20,000 base units of USDC, which with 6 decimals equals $0.02 USD per request.
The broader lowpaymentfee.com platform advertises a suite of pay-per-request APIs spanning data analytics, AI/ML inference (sentiment analysis, summarization, classification, embeddings), finance/Web3 data (price feeds, exchange rates, token quotes, gas estimates), and infrastructure utilities (geocoding, validation, conversion, generation). All endpoints are listed at $0.02 per request with no API keys, no rate limits, and no minimum commitments. However, the crawled documentation pages (docs, api, pricing, README) all returned only a "Connect wallet" prompt with no substantive content, so the actual behavior and response schemas of these endpoints remain unverified.
The x402 challenge was successfully captured (HTTP 402 with a well-formed accepts block), confirming the endpoint is live. The payment is directed to address 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3 with a 300-second timeout. No OpenAPI spec, request/response schemas, or example payloads are available, so the exact input parameters and output format for this invoice endpoint are unknown.
Capabilities
Use cases
- —Retrieving or processing a specific Stripe invoice via a crypto-paid API call
- —Programmatic invoice access without traditional API key provisioning
- —Agent-driven payment flows where USDC on Base settles per-request costs
Fit
Best for
- —Developers wanting keyless, pay-per-use access to invoice data
- —AI agents that can settle x402 payments autonomously on Base
- —Projects already holding USDC on Base looking for low-friction API access
Not for
- —Users needing detailed API documentation or guaranteed SLAs before integrating
- —High-volume batch invoice processing where $0.02/call adds up significantly
- —Anyone without a Base-compatible wallet or USDC holdings
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/stripe/invoices/145 \
-H "X-PAYMENT: <x402-payment-token>" \
-H "Content-Type: application/json"Endpoint
Quality
The x402 challenge is live and well-formed, confirming the endpoint exists and pricing is clear ($0.02 USDC on Base). However, there is no OpenAPI spec, no request/response schema, no documentation beyond a wallet-connect prompt, and the specific purpose of this invoice endpoint is only inferable from the URL path. Effectively a stub listing.
Warnings
- —No OpenAPI or schema available — request parameters and response format are unknown
- —All documentation pages (docs, api, pricing, README) returned only 'Connect wallet' with no content
- —The specific behavior of /api/v1/stripe/invoices/145 is unclear — it may be a demo or placeholder
- —No examples or error handling documentation available
Citations
- —The endpoint returns a 402 challenge with maxAmountRequired of 20000 base units of USDC on Base networkhttps://lowpaymentfee.com/api/v1/stripe/invoices/145
- —All endpoints are priced at $0.02 per request with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —USDC asset contract is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/stripe/invoices/145
- —Payment is directed to address 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3 with 300-second timeouthttps://lowpaymentfee.com/api/v1/stripe/invoices/145