x402-gated Stripe invoice endpoint on Base, pay-per-call with USDC.
What it does
This endpoint at lowpaymentfee.com exposes a Stripe invoice resource (`/api/v1/stripe/invoices/118`) behind an x402 payment challenge. When called without payment, it returns a 402 with an x402 v1 challenge requiring USDC on the Base network. The maximum amount required is 20,000 base units of USDC (6 decimals), which equals $0.02 per request.
The provider's landing page advertises a broad catalog of pay-per-call APIs spanning data & analytics, AI & ML (sentiment analysis, summarization, classification, embeddings), finance & Web3 (price feeds, exchange rates, token quotes, gas estimates), and infrastructure utilities (geocoding, validation, conversion, generation) — all priced at $0.02 per request. This specific endpoint appears to be a Stripe invoice retrieval or interaction endpoint, though the exact response payload is undocumented. The x402 challenge specifies the output MIME type as `application/json` and the HTTP method as POST.
No OpenAPI schema, detailed documentation, or example responses were found in the crawl. The docs, API, pricing, and README pages all returned only a "Connect wallet" prompt with no substantive content. Without documentation of the request body format or response schema, agents will need to discover the interface experimentally or rely solely on the x402 challenge metadata.
Capabilities
Use cases
- —Retrieving or interacting with a Stripe invoice programmatically via x402 micropayment
- —Agent-driven invoice lookup without API keys using on-chain USDC payment
- —Integrating pay-per-call invoice data into automated financial workflows
Fit
Best for
- —Agents that can settle x402 payments in USDC on Base
- —Developers wanting keyless, pay-per-use access to Stripe invoice data
- —Automated systems needing on-demand invoice retrieval without subscription commitments
Not for
- —Users who need detailed API documentation or response schema before integrating
- —High-volume invoice processing where per-call pricing adds up
- —Anyone without a Base-compatible USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/stripe/invoices/118
# Returns 402 with x402 challenge; attach X-PAYMENT header with valid USDC payment proof on Base to access the resource.Endpoint
Quality
The endpoint is live and returns a valid x402 challenge with clear pricing ($0.02 USDC on Base). However, there is no documentation of the request body, response schema, or what the Stripe invoice endpoint actually returns. All doc pages are empty beyond a wallet-connect prompt. This is effectively a stub listing.
Warnings
- —No API documentation available — docs, pricing, and README pages all show only 'Connect wallet' with no content
- —Request body schema for the POST endpoint is unknown
- —Response payload structure is undocumented
- —The specific purpose of /api/v1/stripe/invoices/118 (read vs. write, what data is returned) is unclear
- —Provider site appears to be a demo or early-stage catalog with many advertised endpoints but no substantive documentation
Citations
- —The endpoint returns a 402 x402 v1 challenge requiring USDC on Base network with maxAmountRequired of 20000 base unitshttps://lowpaymentfee.com/api/v1/stripe/invoices/118
- —USDC asset address is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/stripe/invoices/118
- —All APIs on the site are priced at $0.02 per request with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —The provider advertises categories including Data & Analytics, AI & ML, Finance & Web3, and Infrastructurehttps://lowpaymentfee.com