Pay-per-call API platform on Base via x402 — data, AI, finance, and utility endpoints at $0.02/request.
What it does
lowpaymentfee.com is an x402-enabled API platform that offers a collection of endpoints spanning data analytics, AI/ML inference, finance/Web3, and infrastructure utilities. All endpoints are pay-per-request using USDC on the Base network, with no API keys, no rate limits, and no commitments required. The specific endpoint at `/api/v1/charges/285` is labeled "Premium API Access" and accepts POST requests settled via the x402 exact payment scheme.
The platform advertises a flat $0.02 per request across its listed endpoints. The probed endpoint's x402 challenge shows a maxAmountRequired of 20000 base units of USDC (contract 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Base), which equals $0.02 given USDC's 6 decimals. Categories of available APIs include metrics, reports, data export, insights, sentiment analysis, text summarization, classification, embeddings, price feeds, exchange rates, token quotes, gas estimates, geocoding, validation, conversion, and generation.
Documentation is extremely sparse — the /docs, /api, /pricing, and /README pages all render only a "Connect wallet" prompt with no further content. There is no OpenAPI spec, no request/response schema documentation, and no examples available. The exact functionality behind the "Premium API Access" charge endpoint (285) is unclear, as it does not map to any of the named endpoints listed on the homepage. Agents should treat this endpoint with caution until more documentation is available.
Capabilities
Use cases
- —Agent-driven pay-per-call access to AI inference endpoints like sentiment analysis or summarization
- —Fetching real-time financial data (prices, exchange rates, gas estimates) without subscription
- —On-demand geocoding or data validation without API key management
Fit
Best for
- —AI agents needing frictionless, keyless API access via x402
- —Developers who want pay-as-you-go pricing with no minimum commitment
- —Web3-native applications settling microtransactions on Base
Not for
- —Users needing detailed API documentation or guaranteed SLAs
- —High-volume batch processing where per-request pricing becomes expensive
- —Applications requiring non-crypto payment methods
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/charges/285 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is live and returns a valid x402 challenge with clear pricing ($0.02 USDC on Base). However, documentation is essentially nonexistent — all doc pages show only 'Connect wallet'. There is no OpenAPI spec, no request/response schema, no examples, and the specific purpose of the /charges/285 endpoint is undocumented. The listing is effectively a stub.
Warnings
- —No documentation available — /docs, /api, /pricing, and /README pages all render only 'Connect wallet'
- —No OpenAPI or schema specification found
- —The specific endpoint /api/v1/charges/285 ('Premium API Access') does not correspond to any named endpoint on the homepage; its exact functionality is unknown
- —No request or response examples available to verify what the endpoint actually returns
Citations
- —Platform advertises $0.02/request flat pricing with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —x402 challenge returns maxAmountRequired of 20000 base units of USDC (0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Basehttps://lowpaymentfee.com/api/v1/charges/285
- —Available API categories include Data & Analytics, AI & Machine Learning, Finance & Web3, and Infrastructurehttps://lowpaymentfee.com
- —Documentation pages (/docs, /api, /pricing, /README) render only 'Connect wallet' with no further contenthttps://lowpaymentfee.com/docs