x402-gated Stripe invoice endpoint on Base, paid per-call in USDC.
What it does
This endpoint at lowpaymentfee.com provides "Premium API Access" behind an x402 payment challenge. It is part of a broader platform that offers a variety of pay-per-request APIs spanning data & analytics, AI/ML inference, finance & Web3 data, and infrastructure utilities — all gated via the x402 protocol on the Base network and settled in USDC.
The specific endpoint `/api/v1/stripe/invoices/81` appears to be a Stripe invoice-related resource. The x402 challenge indicates a maximum cost of 20,000 base units of USDC (0x8335… on Base), which equals $0.02 per request (USDC uses 6 decimals). The platform advertises uniform $0.02/request pricing across all its endpoints, with no API keys, no rate limits, and no minimum commitments required. Payment is made inline via the x402 `X-PAYMENT` header using the "exact" scheme.
Documentation on the site 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 (returns a well-formed 402 challenge), but the actual functionality behind the paywall is unclear beyond the "Premium API Access" label and the Stripe invoices path.
Capabilities
Use cases
- —Programmatically accessing Stripe invoice data via a crypto-settled pay-per-call model
- —Agent-driven workflows that need to fetch or create invoice records without traditional API keys
- —Integrating USDC micropayments into invoice retrieval pipelines
Fit
Best for
- —Developers who want keyless, pay-per-use API access settled in USDC on Base
- —AI agents that can handle x402 payment challenges natively
- —Users who prefer crypto micropayments over subscription-based API billing
Not for
- —Users who need detailed API documentation or OpenAPI specs before integrating
- —High-volume consumers who would benefit from bulk/subscription pricing
- —Anyone without a Base-compatible USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/stripe/invoices/81 \
-H "X-PAYMENT: <x402-payment-token>" \
-H "Content-Type: application/json"Endpoint
Quality
The endpoint is confirmed live with a valid x402 challenge and clear pricing ($0.02/request in USDC on Base). However, there is no OpenAPI spec, no request/response schema, no documentation beyond a wallet-connect prompt, and no examples. The actual functionality behind the paywall is undocumented, making this effectively a stub listing.
Warnings
- —No API documentation available — docs, pricing, and README pages all show only 'Connect wallet'
- —No OpenAPI or JSON schema describing request parameters or response format
- —Actual functionality of the /api/v1/stripe/invoices/81 endpoint is unknown beyond its path name
- —No request or response examples available
Citations
- —The endpoint returns a valid x402 challenge with maxAmountRequired of 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/stripe/invoices/81
- —The platform advertises $0.02/request pricing 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/81