x402-gated premium API access on Base, paid per-call in USDC.
What it does
This endpoint at lowpaymentfee.com provides "Premium API Access" behind an x402 paywall. The endpoint is located at `/api/v1/stripe/subscriptions/29` and accepts POST requests. Payment is settled on the Base network using USDC (contract 0x8335…2913) via the x402 "exact" scheme.
The x402 challenge advertises a maxAmountRequired of 20,000 base units. Since USDC uses 6 decimals, this converts to $0.02 per request, consistent with the site's stated pricing of $0.02/request across all its endpoints. The provider advertises no API keys, no rate limits, and instant access.
The broader lowpaymentfee.com platform offers multiple API categories including Data & Analytics, AI & Machine Learning, Finance & Web3, and Infrastructure utilities. However, this specific endpoint's path (`/stripe/subscriptions/29`) suggests it may relate to a subscription or Stripe-integration resource rather than the general-purpose APIs listed on the homepage. The exact response payload and functionality of this particular endpoint are not documented in the crawled material — the description simply reads "Premium API Access" with no further detail on what data or service is returned.
Capabilities
Use cases
- —Programmatic access to a premium API resource with per-call USDC micropayments
- —Agent-driven workflows that need keyless, pay-as-you-go API consumption on Base
- —Demonstrating x402 payment protocol integration for subscription-style endpoints
Fit
Best for
- —Developers experimenting with x402 payment flows on Base
- —Agents that can settle USDC payments on Base L2
- —Use cases requiring keyless, no-signup API access
Not for
- —Users who need detailed documentation or guaranteed SLAs before integrating
- —Applications requiring fiat-only payment rails with no crypto involvement
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/stripe/subscriptions/29
# Returns 402 with x402 challenge; attach X-PAYMENT header with signed USDC payment on Base to access.Example
Response
{
"error": "X-PAYMENT header is required",
"accepts": [
{
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"extra": {
"name": "USD Coin",
"version": "2"
},
"payTo": "0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3",
"scheme": "exact",
"network": "base",
"mimeType": "application/json",
"resource": "https://lowpaymentfee.com/api/v1/stripe/subscriptions/29",
"description": "Premium API Access",
"maxAmountRequired": "20000",
"maxTimeoutSeconds": 300
}
],
"x402Version": 1
}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 what the endpoint actually returns upon successful payment, no request/response schema, and the crawled docs/pricing/API pages are all blank ('Connect wallet'). The endpoint path suggests a Stripe subscription resource but nothing explains the actual functionality.
Warnings
- —No documentation available — all doc pages render only 'Connect wallet' with no content
- —The endpoint path '/api/v1/stripe/subscriptions/29' is not listed among the advertised APIs on the homepage; its actual functionality is unknown
- —No request body schema or response schema documented
- —No OpenAPI spec or AI plugin manifest found
Citations
- —Pricing is $0.02 per request with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —x402 challenge returns maxAmountRequired of 20000 base units in USDC on Base networkhttps://lowpaymentfee.com/api/v1/stripe/subscriptions/29
- —USDC asset contract is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/stripe/subscriptions/29