Pay-per-call notification endpoint on Base via x402 — $0.02 per request in USDC.
What it does
This endpoint at `/api/v1/notifications/67` is part of the lowpaymentfee.com platform, which offers a collection of x402-protocol pay-per-request APIs spanning data analytics, AI/ML inference, finance, crypto, and utility services. The specific endpoint being listed here is labeled "Premium API Access" and accepts POST requests, settling payments in USDC on the Base network at $0.02 per call (20,000 base units of USDC with 6 decimals). No API keys or accounts are required — callers authenticate purely via the x402 payment header.
The broader lowpaymentfee.com platform advertises endpoints across several categories including sentiment analysis, text summarization, classification, embeddings, price feeds, exchange rates, geocoding, validation, conversion, and data export — all at the same $0.02/request price point. However, this specific listing covers the `/api/v1/notifications/67` resource, whose exact functionality beyond "Premium API Access" is not documented in the crawled material. The endpoint is live and returns a proper x402 402 challenge with version 1 of the protocol.
Payment is made to address `0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3` using USDC (`0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913`) on Base. The maximum timeout for payment settlement is 300 seconds. The platform advertises no rate limits and instant access with no minimums or commitments.
Capabilities
Use cases
- —Triggering or retrieving notifications via a pay-per-call model without needing an API key
- —Integrating notification functionality into agent workflows that settle payments on Base in USDC
- —Testing x402 protocol integrations with a low-cost live endpoint
Fit
Best for
- —Developers exploring x402 pay-per-request patterns
- —Agents needing keyless API access with crypto micropayments
- —Projects already operating on the Base L2 network with USDC
Not for
- —Users who need detailed documentation on the notification payload and behavior before calling
- —High-volume notification use cases where per-call pricing may add up compared to subscription models
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/notifications/67 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-header>"Endpoint
Quality
The endpoint is live and returns a valid x402 402 challenge, but there is no documentation on what the /notifications/67 endpoint actually does, what request body it expects, or what it returns. The crawled pages provide only a high-level catalog listing and pricing info. The specific endpoint's purpose is unclear beyond the generic 'Premium API Access' label.
Warnings
- —The exact functionality of /api/v1/notifications/67 is undocumented — 'Premium API Access' is the only description available.
- —No request body schema or response schema is provided; callers must discover behavior empirically.
- —The /api, /pricing, and /README pages all returned only a 'Connect wallet' prompt with no useful content.
- —The notification endpoint path includes a numeric ID (67) whose meaning is unexplained.
Citations
- —The endpoint returns a 402 challenge with maxAmountRequired of 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/notifications/67
- —USDC contract address on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/notifications/67
- —Platform pricing is $0.02 per request with no API keys, no rate limits, and no minimumshttps://lowpaymentfee.com
- —The platform offers APIs across data/analytics, AI/ML, finance/Web3, and infrastructure categorieshttps://lowpaymentfee.com