x402-gated API platform on Base offering data, AI, finance, and utility endpoints at $0.02/request.
What it does
lowpaymentfee.com is an x402-protocol API marketplace that gates access to a variety of endpoints behind per-request USDC micropayments on the Base network. The platform advertises four categories of APIs: 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 priced at $0.02 per request with no API keys, no rate limits, and no minimum commitments required.
The specific endpoint `/api/v1/trades/82` is listed as "Premium API Access" and returns a valid x402 402 challenge. Its payment challenge specifies a maxAmountRequired of 20,000 base units of USDC (0x8335…2913 on Base, 6 decimals), which equals $0.02. Payment is settled on-chain via the x402 "exact" scheme to the payTo address. The endpoint accepts POST requests and returns application/json.
Note that while the landing page lists many endpoint categories, the crawled documentation, pricing, and other subpages returned only a "Connect wallet" prompt with no additional technical detail. There is no OpenAPI spec, no request/response schema documentation, and no examples available. The actual functionality behind `/api/v1/trades/82` is unclear — the name "trades" and ID "82" suggest it may return trade data, but this is not documented.
Capabilities
Use cases
- —Accessing trade data behind a per-call micropayment without needing an API key
- —Programmatic agents purchasing API responses on-the-fly using x402 USDC payments
- —Integrating low-cost, keyless API access into automated workflows on Base
Fit
Best for
- —Developers wanting keyless, pay-per-use API access
- —AI agents that can settle x402 payments autonomously
- —Users who prefer on-chain micropayments over subscription billing
Not for
- —Users who need detailed API documentation or OpenAPI specs before integrating
- —High-volume consumers who would benefit from bulk pricing or subscriptions
- —Anyone without a Base-compatible USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/trades/82 \
-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, there is no OpenAPI spec, no request/response schema, no documentation beyond a landing page listing, and the specific purpose of /api/v1/trades/82 is undocumented. The docs, pricing, and README pages all render only a wallet-connect prompt with no useful content.
Warnings
- —No OpenAPI or schema documentation available for any endpoint
- —The purpose and expected input/output of /api/v1/trades/82 is not documented anywhere in the crawl
- —Documentation pages (/docs, /pricing, /README, /api) return only a 'Connect wallet' prompt with no technical content
- —Cannot verify what data or functionality this specific endpoint actually provides
Citations
- —The platform lists APIs across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categories, all priced at $0.02/requesthttps://lowpaymentfee.com
- —No API keys, no rate limits, instant access, Base networkhttps://lowpaymentfee.com
- —x402 challenge returns maxAmountRequired of 20000 base units of USDC (0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Basehttps://lowpaymentfee.com/api/v1/trades/82