Pay-per-call API platform on Base (USDC) covering data, AI, finance, and utility endpoints at $0.02/request.
What it does
lowpaymentfee.com is an x402-enabled API platform that offers a broad catalog of pay-per-request endpoints settled in USDC on the Base network. The specific endpoint at `/api/v1/payments/100` is listed as "Premium API Access" and charges up to $0.02 per call (20,000 base units of USDC with 6 decimals). Payment is handled via the x402 protocol — no API keys, accounts, or rate limits are required; callers simply attach an X-PAYMENT header with a valid payment proof.
The platform advertises four endpoint categories: Data & Analytics (metrics, reports, data export, insights), AI & Machine Learning (sentiment analysis, text summarization, classification, embeddings), Finance & Web3 (price feeds, exchange rates, token quotes, gas estimates), and Infrastructure utilities (geocoding, validation, conversion, generation). All endpoints are listed at the same $0.02 per request price point.
Documentation is extremely thin — the /docs, /pricing, /api, and /README pages all render only a "Connect wallet" prompt with no further technical detail. There is no OpenAPI spec, no request/response schema documentation, and no usage examples available from the crawl. The x402 challenge confirms the endpoint is live and accepting POST requests, but the actual behavior and response format of `/api/v1/payments/100` (or any other listed endpoint) cannot be verified from available materials.
Capabilities
Use cases
- —Agents needing on-demand AI inference (sentiment, summarization, classification, embeddings) without signup
- —Fetching real-time financial data like token quotes, gas estimates, or exchange rates via micropayment
- —Geocoding or data validation as a utility service paid per request in USDC
Fit
Best for
- —AI agents that need keyless, pay-per-call access to diverse API endpoints
- —Developers who want to avoid API key management and subscription commitments
- —Web3-native applications settling microtransactions on Base
Not for
- —High-volume production workloads where $0.02/request adds up quickly without bulk discounts
- —Users who need detailed API documentation, SLAs, or guaranteed uptime
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/payments/100 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-proof>"Endpoint
Quality
The x402 challenge is live and confirms pricing and network details, but documentation is effectively nonexistent — every doc page just shows 'Connect wallet'. No OpenAPI spec, no request/response schemas, no usage examples. The actual functionality behind '/api/v1/payments/100' and other listed endpoints is unverifiable.
Warnings
- —Documentation pages (/docs, /pricing, /api, /README) all return only 'Connect wallet' with no technical content
- —No OpenAPI or schema available — request and response formats are unknown
- —The specific purpose of /api/v1/payments/100 ('Premium API Access') is unclear; it may be a generic or demo endpoint
- —No robots.txt or agents.txt found
Citations
- —The endpoint returns a 402 x402 challenge with maxAmountRequired of 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/payments/100
- —All listed endpoints are priced at $0.02 per request with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —The platform offers endpoints in four categories: Data & Analytics, AI & Machine Learning, Finance & Web3, and Infrastructurehttps://lowpaymentfee.com
- —USDC asset address is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Base networkhttps://lowpaymentfee.com/api/v1/payments/100