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 54) 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 at 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 and crypto market data, 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 specific endpoint being listed here (/api/v1/stripe/invoices/54) is labeled "Premium API Access" and does not clearly map to any of the documented API categories.
Documentation is extremely sparse. The docs, API, pricing, and README pages all render only a "Connect wallet" prompt with no further technical detail. There is no OpenAPI spec, no request/response schema documentation, and no usage examples available from the crawled material. The endpoint is confirmed live via a valid 402 challenge response.
Capabilities
Use cases
- —Retrieving Stripe invoice data via a crypto-settled paywall
- —Programmatic access to invoice #54 without traditional API keys
- —Agent-driven payment and data retrieval in a single HTTP round-trip
Fit
Best for
- —Developers experimenting with x402 payment protocol
- —Agents that can settle USDC payments on Base automatically
- —Use cases requiring keyless, pay-per-call API access
Not for
- —Users needing detailed API documentation or OpenAPI specs before integrating
- —Production workflows requiring well-documented request/response schemas
- —Bulk or high-volume invoice retrieval (no batch endpoint documented)
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/stripe/invoices/54
# Returns 402 with x402 challenge; attach X-PAYMENT header with signed USDC payment on Base to access.Endpoint
Quality
The endpoint is confirmed live via a valid 402 challenge, but there is no documentation, no request/response schema, no examples, and the purpose of this specific invoice endpoint is unclear. Docs pages are empty beyond a wallet-connect prompt. This is effectively a stub listing.
Warnings
- —No OpenAPI spec or request/response schema available
- —All documentation pages (docs, API, pricing, README) render only 'Connect wallet' with no content
- —The specific endpoint /api/v1/stripe/invoices/54 is not described in the site's API catalog — its purpose and expected input/output are unknown
- —No examples of successful responses are available
Citations
- —Endpoint returns a valid x402 challenge with status 402, confirming it is livehttps://lowpaymentfee.com/api/v1/stripe/invoices/54
- —Payment is in USDC (USD Coin) on Base network, maxAmountRequired 20000 base units ($0.02)https://lowpaymentfee.com/api/v1/stripe/invoices/54
- —Platform advertises $0.02/request pricing with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —Docs, API, pricing, and README pages show only 'Connect wallet' with no further contenthttps://lowpaymentfee.com/docs