Pay-per-call API suite on Base (USDC) covering analytics, AI, finance, and utilities at $0.02/request.
What it does
lowpaymentfee.com is an x402-enabled API platform that offers a broad collection of endpoints spanning data analytics, AI/ML inference, finance/Web3 data, and general-purpose utilities. Every endpoint is priced at $0.02 per request, settled in USDC on the Base network. There are no API keys, no rate limits, and no minimum commitments — callers simply attach an x402 payment header to each request.
The specific endpoint at `/api/v1/messages/103` is listed as "Premium API Access" and accepts POST requests. Its x402 challenge advertises a maximum cost of 20,000 base units of USDC (0x8335…2913 on Base), which equals $0.02 given USDC's 6 decimals. The payment is sent to address 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3 with a 300-second timeout.
The broader platform advertises additional endpoints including sentiment analysis, text summarization, classification, embeddings, price feeds, exchange rates, token quotes, gas estimates, geocoding, validation, conversion, and generation — all at the same $0.02 price point. However, no OpenAPI schema, request/response examples, or detailed documentation were found during crawling; the docs, pricing, and README pages all returned only a "Connect wallet" prompt with no substantive content. The exact input format and response structure for this endpoint remain unknown.
Capabilities
Use cases
- —Accessing AI inference (sentiment, summarization, classification, embeddings) without API key management
- —Fetching real-time crypto quotes, gas estimates, and exchange rates on a per-call basis
- —Running geocoding, validation, or data conversion tasks with instant micropayment settlement
Fit
Best for
- —Agents and bots that need keyless, on-demand API access paid per call
- —Developers wanting low-friction access to diverse utility endpoints without subscriptions
- —Web3-native applications that can settle USDC payments on Base
Not for
- —High-volume production workloads where $0.02/request adds up (no bulk discounts documented)
- —Users who need detailed API documentation, schemas, or guaranteed SLAs before integrating
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/messages/103 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-header>" \
-d '{}'Endpoint
Quality
The endpoint is live and returns a valid x402 challenge, and the landing page lists available endpoints with pricing. However, there is no OpenAPI schema, no request/response examples, and no substantive documentation — the docs/pricing/README pages are all empty behind a wallet-connect gate. The purpose of this specific '/messages/103' endpoint is unclear beyond its generic 'Premium API Access' label.
Warnings
- —No OpenAPI or schema documentation available for any endpoint
- —Docs, pricing, and README pages return only a 'Connect wallet' prompt with no content
- —The specific purpose and expected input/output of /api/v1/messages/103 is undocumented
- —No request or response examples could be obtained
Citations
- —The endpoint returns a 402 challenge with maxAmountRequired of 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/messages/103
- —All endpoints are priced at $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —The platform offers endpoints across Data & Analytics, AI & Machine Learning, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com