Pay-per-call API platform on Base (USDC) offering data, AI, finance, and utility endpoints at $0.02/request.
What it does
lowpaymentfee.com is an x402-enabled API platform that provides a broad catalog of pay-per-request endpoints settled in USDC on the Base network. The specific endpoint at `/api/v1/payments/372` is listed as "Premium API Access" and costs $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 wider 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 listed endpoints share the same $0.02/request pricing.
Documentation is extremely sparse — 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 crawled material. The x402 challenge confirms the endpoint is live and accepts POST requests returning application/json, but the actual request body format and response structure for this specific endpoint are unknown.
Capabilities
Use cases
- —Agents needing on-demand API access without pre-registration or API keys
- —Micropayment-gated data retrieval for analytics or financial data
- —AI inference tasks (sentiment, summarization, classification) paid per call
- —Utility operations like geocoding or data conversion with instant crypto settlement
Fit
Best for
- —Developers and agents wanting zero-signup, pay-as-you-go API access
- —Crypto-native workflows that can settle USDC on Base
- —Low-volume or bursty usage patterns where per-request pricing is economical
Not for
- —High-volume production workloads needing guaranteed SLAs and detailed documentation
- —Users without USDC on Base or unfamiliar with x402 payment protocol
- —Applications requiring well-documented request/response schemas before integration
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/payments/372 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-proof>" \
-d '{}'Endpoint
Quality
The x402 challenge is live and confirms pricing and settlement details, but documentation is effectively nonexistent — all doc pages show only 'Connect wallet'. No OpenAPI spec, no request/response schemas, and no examples are available. The endpoint's actual functionality behind 'Premium API Access' is unclear.
Warnings
- —Documentation pages (/docs, /pricing, /api, /README) all render only 'Connect wallet' with no usable content
- —No OpenAPI or schema documentation available — request and response formats are unknown
- —The specific purpose of /api/v1/payments/372 ('Premium API Access') is not explained anywhere in the crawled material
- —The broad catalog of endpoints (AI, finance, data, utils) is advertised but none have documented input/output contracts
Citations
- —The endpoint returns a 402 x402 challenge with maxAmountRequired of 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/payments/372
- —All listed 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 in four categories: Data & Analytics, AI & Machine Learning, Finance & Web3, and Infrastructurehttps://lowpaymentfee.com
- —USDC asset contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/payments/372