Pay-per-call notification endpoint on Base via x402, settled in USDC at $0.02/request.
What it does
This endpoint at lowpaymentfee.com provides a "Premium API Access" notification resource at `/api/v1/notifications/73`. It is part of a broader platform offering dozens of pay-per-call API endpoints spanning data analytics, AI/ML inference, finance/Web3 data, and infrastructure utilities — all priced at $0.02 per request and settled in USDC on the Base network via the x402 payment protocol.
The specific endpoint probed (`/api/v1/notifications/73`) returned a valid 402 challenge confirming it is live. The challenge specifies payment of up to 20,000 base units of USDC (0x8335…2913 on Base), which equals $0.02 given USDC's 6 decimals. Payment is made to address 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3 with a 300-second timeout. The endpoint accepts HTTP POST requests and returns `application/json`.
The platform advertises no API keys, no rate limits, and instant access. However, documentation is extremely sparse — there is no OpenAPI spec, no request/response schema, and no explanation of what the notifications endpoint actually returns or what parameters it accepts. The crawled docs and pricing pages rendered only a "Connect wallet" prompt with no additional detail. Without knowing the request body format or response structure, callers will need to experiment or contact the provider.
Capabilities
Use cases
- —Sending or retrieving notifications via a pay-per-call model without API key management
- —Integrating low-cost notification triggers into agent workflows settled on-chain
- —Testing x402 payment protocol integrations with a live, inexpensive endpoint
Fit
Best for
- —Developers exploring x402 protocol payment flows
- —Agents needing simple pay-per-call notification endpoints
- —Projects wanting no-signup, no-rate-limit API access on Base
Not for
- —Production notification systems requiring documented request/response contracts
- —Use cases needing guaranteed SLAs or support, since documentation is minimal
- —High-volume notification pipelines where $0.02/call adds up quickly
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/notifications/73 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>" \
-d '{}'Endpoint
Quality
The endpoint is live (valid 402 challenge captured) and pricing is clear ($0.02 USDC on Base). However, there is no OpenAPI spec, no request/response schema, no documentation of what the notifications endpoint does, and the crawled pages beyond the landing page returned only wallet-connect prompts. The listing is effectively a stub with confirmed liveness.
Warnings
- —No OpenAPI or schema documentation available — request body and response format are unknown
- —The specific purpose of /api/v1/notifications/73 is undocumented; 'Premium API Access' is a generic label
- —Crawled /api, /pricing, and /README pages all returned only 'Connect wallet' with no useful content
- —No examples or integration guides found
Citations
- —Endpoint returns 402 with x402 challenge specifying USDC on Base, maxAmountRequired 20000 (=$0.02)https://lowpaymentfee.com/api/v1/notifications/73
- —Platform advertises $0.02/request pricing with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —USDC asset contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/notifications/73