Pay-per-call API suite on Base (USDC) covering analytics, AI, finance, and utilities at $0.02/request.
What it does
lowpaymentfee.com offers a collection of x402-enabled API endpoints settled in USDC on the Base network. The specific endpoint at `/api/resource/1` is described as "Premium API Access" and costs up to $0.02 per request (maxAmountRequired of 20,000 base units of USDC, which is 6-decimal, equaling $0.02). No API keys or rate limits are advertised — callers simply attach an x402 payment header to each request.
The broader platform lists endpoints across four 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 are priced at $0.02 per request.
Documentation is extremely thin — the /docs, /api, /pricing, and /README pages all returned only a "Connect wallet" prompt with no further content. There is no OpenAPI spec, no request/response schema documentation, and no example payloads available. The endpoint is live (returns a valid 402 x402 challenge), but without documentation it is unclear what request body `/api/resource/1` expects or what it returns. The outputSchema in the challenge only indicates it accepts HTTP POST requests.
Capabilities
Use cases
- —Accessing AI inference endpoints (sentiment, summarization, classification, embeddings) without API key management
- —Fetching real-time financial data like token quotes, gas estimates, and exchange rates on a per-call basis
- —Running analytics queries and data exports with per-request USDC micropayments
- —Geocoding, validation, and data conversion via utility endpoints
Fit
Best for
- —Agents or applications that need keyless, pay-per-use API access settled on-chain
- —Developers wanting low-friction access to multiple API categories without subscriptions
- —Crypto-native workflows that can attach x402 payment headers natively
Not for
- —Users who need detailed API documentation or OpenAPI specs before integrating
- —High-volume consumers who would benefit from bulk pricing or subscription plans
- —Applications that cannot handle USDC payments on the Base network
Quick start
curl -X POST https://lowpaymentfee.com/api/resource/1 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is live and returns a valid x402 402 challenge, but documentation is essentially nonexistent — all doc pages show only 'Connect wallet'. There is no OpenAPI spec, no request/response examples, and no description of what /api/resource/1 actually does beyond the generic label 'Premium API Access'. Pricing is clear but functionality is opaque.
Warnings
- —No API documentation available — /docs, /api, /pricing, and /README pages all return only 'Connect wallet'
- —No OpenAPI or schema specification provided for any endpoint
- —The specific endpoint /api/resource/1 is not listed among the advertised API routes on the homepage; its purpose is unclear
- —Request and response formats are entirely undocumented
Citations
- —The endpoint returns a 402 x402 challenge with maxAmountRequired of 20000 base units of USDC on Base networkhttps://lowpaymentfee.com/api/resource/1
- —All listed endpoints are priced at $0.02 per request with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —The platform lists endpoints across Data & Analytics, AI & Machine Learning, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com
- —USDC asset address 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Base networkhttps://lowpaymentfee.com/api/resource/1