Pay-per-call notification endpoint on Base via x402, settled in USDC at $0.02/request.
What it does
This endpoint at `/api/v1/notifications/5` is part of the lowpaymentfee.com platform, which offers a suite of pay-per-request APIs spanning data & analytics, AI/ML inference, finance & Web3, and infrastructure utilities. All endpoints are gated via the x402 protocol, requiring a USDC payment on the Base network for each call. The specific endpoint listed here is described as "Premium API Access" and costs $0.02 per request (20,000 base units of USDC with 6 decimals).
The platform advertises a simple pricing model: $0.02 per request across all endpoints, with no API keys, no rate limits, no minimums, and instant access. Payment is settled on-chain to address `0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3` using USDC (`0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913`) on Base. The x402 challenge was successfully captured with version 1 of the protocol, confirming the endpoint is live.
However, the specific functionality of the `/api/v1/notifications/5` endpoint is unclear. The provider's landing page lists many API categories (analytics, AI, finance, infrastructure) but does not mention a notifications endpoint. No OpenAPI schema, request/response examples, or detailed documentation were found. The `/api`, `/pricing`, and `/README` pages all returned only a "Connect wallet" prompt with no additional content. As a result, the actual behavior and response format of this endpoint remain unknown.
Capabilities
Use cases
- —Sending or retrieving notifications via a pay-per-call model without API key management
- —Integrating low-cost notification services into agent workflows settled on Base
- —Testing x402 protocol payment flows with a live endpoint
Fit
Best for
- —Developers exploring x402 pay-per-request patterns
- —Agent-based systems needing keyless API access with on-chain payment
- —Low-volume notification use cases where per-call pricing is preferred
Not for
- —High-volume notification workloads where per-call costs add up quickly
- —Users who need detailed documentation or guaranteed SLAs before integrating
- —Anyone without a Base-compatible USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/notifications/5 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>" \
-d '{}'Endpoint
Quality
The endpoint is live (402 challenge captured) and pricing is clear ($0.02 USDC on Base), but there is no documentation, no OpenAPI schema, no request/response examples, and the specific purpose of the /notifications/5 path is undocumented. The landing page does not list a notifications category at all.
Warnings
- —The /api/v1/notifications/5 endpoint is not listed on the provider's landing page among available APIs — its actual functionality is unknown.
- —No OpenAPI spec, request schema, or response schema is available.
- —The /api, /pricing, and /README pages returned no useful content beyond 'Connect wallet'.
- —The endpoint's purpose ('Premium API Access') is a generic label that does not describe what the endpoint actually does.
Citations
- —The endpoint returns a 402 x402 challenge requesting 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/notifications/5
- —USDC contract address on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/notifications/5
- —Platform pricing is $0.02 per request with no API keys, no rate limits, and no minimumshttps://lowpaymentfee.com
- —The landing page lists APIs in categories: Data & Analytics, AI & Machine Learning, Finance & Web3, and Infrastructure — but no notifications categoryhttps://lowpaymentfee.com