Pay-per-call notification endpoint on Base via x402 — $0.02 per request in USDC.
What it does
This endpoint at lowpaymentfee.com provides a "Premium API Access" notification resource at `/api/v1/notifications/25`. It is part of a broader platform offering dozens of pay-per-call APIs spanning data & analytics, AI/ML inference, finance/Web3, and infrastructure utilities — all priced at $0.02 per request and settled in USDC on the Base network via the x402 protocol.
The specific `/api/v1/notifications/25` endpoint accepts POST requests and returns JSON. Payment is handled inline: callers attach an `X-PAYMENT` header containing a signed x402 payment for up to 20,000 base units of USDC (i.e., $0.02, since USDC uses 6 decimals). The payment is sent to address `0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3` on Base mainnet. No API keys, rate limits, or upfront commitments are required — access is instant once payment is included.
Documentation beyond the landing page is sparse. The `/api`, `/pricing`, and `/README` routes all resolve to a wallet-connect stub with no additional detail. There is no OpenAPI spec, no request/response schema documentation, and no example payloads describing what the notifications endpoint actually returns or what POST body it expects. The endpoint is confirmed live (returns a proper 402 challenge), but the actual functionality behind the paywall is unknown from available materials.
Capabilities
Use cases
- —Triggering 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 payment flows against a live endpoint
Fit
Best for
- —Developers experimenting with x402 payment protocol integrations
- —Agents needing simple pay-per-call notification access on Base
- —Projects that want to avoid API key provisioning and subscriptions
Not for
- —Users who need detailed documentation or guaranteed SLAs before integrating
- —High-volume notification pipelines where $0.02/request adds up significantly
- —Anyone requiring non-USDC or non-Base settlement
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/notifications/25 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is confirmed live with a valid 402 challenge and clear pricing ($0.02 USDC on Base). However, there is no OpenAPI spec, no request/response schema, no documentation beyond a landing page listing, and no examples of what the notifications endpoint actually does. The actual functionality behind the paywall is entirely unknown.
Warnings
- —No documentation exists for the /api/v1/notifications/25 endpoint — its purpose and expected request/response format are unknown.
- —No OpenAPI spec, no README content, and /api, /pricing, /README pages are all empty wallet-connect stubs.
- —The broader platform lists many endpoints but none have documented schemas or examples.
- —Actual notification functionality is unverifiable without paying through the paywall.
Citations
- —The endpoint returns a 402 challenge requesting 20,000 base units of USDC on Base (asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913).https://lowpaymentfee.com/api/v1/notifications/25
- —All APIs on the platform are priced at $0.02 per request with no API keys, no rate limits, and instant access on the Base network.https://lowpaymentfee.com
- —Payment is sent to address 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3.https://lowpaymentfee.com/api/v1/notifications/25