x402-gated Stripe invoice endpoint on Base, paying per-call in USDC.
What it does
This endpoint at lowpaymentfee.com provides "Premium API Access" behind an x402 payment challenge. The specific resource path (`/api/v1/stripe/invoices/152`) suggests it returns or processes a Stripe invoice record (invoice #152). Payment is settled on the Base network using USDC (contract 0x8335…2913) with a maximum cost of 0.02 USDC per request (20,000 base units at 6 decimals). The endpoint accepts HTTP POST and returns application/json.
The broader lowpaymentfee.com platform advertises a suite of x402-gated APIs spanning data & analytics, AI/ML inference (sentiment analysis, summarization, classification, embeddings), finance & Web3 (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 — payment is handled entirely via the x402 protocol on Base.
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 crawl. The endpoint is confirmed live (402 challenge captured), but the actual behavior behind the paywall is unknown.
Capabilities
Use cases
- —Retrieving or processing a specific Stripe invoice record via a crypto-settled paywall
- —Demonstrating x402 payment protocol integration for per-call API monetization
- —Programmatic invoice access without traditional API key authentication
Fit
Best for
- —Developers experimenting with x402 payment protocol on Base
- —Agents that can settle USDC micropayments for per-call API access
- —Projects needing keyless, pay-as-you-go API access patterns
Not for
- —Users needing detailed API documentation or schema guarantees before purchasing
- —High-volume invoice processing where $0.02/call adds up significantly
- —Anyone without a Base-compatible USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/stripe/invoices/152 \
-H "X-PAYMENT: <x402-payment-token>" \
-H "Content-Type: application/json"Endpoint
Quality
The endpoint is confirmed live via a valid 402 challenge, 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 no examples. The actual functionality behind the paywall is entirely opaque — the description 'Premium API Access' and path '/stripe/invoices/152' are the only hints.
Warnings
- —No API documentation available — /docs, /api, /pricing, and /README all return only 'Connect wallet'
- —No OpenAPI or schema specification found
- —Actual response format and content behind the paywall are unknown
- —The specific invoice endpoint (/invoices/152) may be a static demo resource rather than a general-purpose API
- —No robots.txt or agents.txt present
Citations
- —Endpoint returns 402 with x402 challenge requiring USDC on Base network, maxAmountRequired 20000 base unitshttps://lowpaymentfee.com/api/v1/stripe/invoices/152
- —USDC asset contract is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/stripe/invoices/152
- —Platform advertises $0.02/request pricing with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —Available API categories include Data & Analytics, AI & ML, Finance & Web3, and Infrastructurehttps://lowpaymentfee.com
- —Documentation pages render only a 'Connect wallet' prompt with no technical contenthttps://lowpaymentfee.com/docs