Pay-per-call premium API access on Base via x402 — $0.02 per request in USDC.
What it does
lowpaymentfee.com hosts a collection of pay-per-request API endpoints accessible via the x402 payment protocol on the Base network. This specific endpoint (`/api/resource/22`) is labeled "Premium API Access" and accepts POST requests. Payment is settled in USDC (contract 0x8335…2913 on Base) at a maximum cost of 20,000 base units, which equals $0.02 per call (USDC uses 6 decimals). No API keys, rate limits, or upfront commitments are required — callers simply attach an X-PAYMENT header with a valid x402 payment proof.
The broader lowpaymentfee.com platform advertises 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 listed endpoints share the same $0.02/request pricing. However, this listing covers only the `/api/resource/22` endpoint, whose specific functionality beyond "Premium API Access" is not documented.
The x402 challenge was successfully captured with version 1, confirming the endpoint is live. The payment timeout is 300 seconds. No OpenAPI schema, detailed request/response documentation, or usage examples were found in the crawl — the docs, pricing, and API pages all returned only a "Connect wallet" prompt with no further content.
Capabilities
Use cases
- —Programmatic access to a premium API resource without needing API keys or subscriptions
- —Agent-driven workflows that pay per call using USDC on Base
- —Testing x402 payment protocol integrations with a low-cost endpoint
Fit
Best for
- —Developers experimenting with x402 payment flows
- —AI agents that need keyless, pay-as-you-go API access
- —Low-cost per-request API consumption settled on-chain
Not for
- —Users who need detailed API documentation or guaranteed SLAs
- —High-throughput use cases where on-chain settlement per request adds latency
- —Anyone without a Base-compatible USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/resource/22 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-proof>"Endpoint
Quality
The endpoint is live and returns a valid x402 402 challenge with clear pricing. However, there is no OpenAPI schema, no request/response documentation, no examples, and the specific functionality of /api/resource/22 is undocumented. The docs and other pages returned only 'Connect wallet' with no usable content.
Warnings
- —The specific functionality of /api/resource/22 is completely undocumented — the description is only 'Premium API Access' with no further detail.
- —No OpenAPI spec, request schema, or response schema is available.
- —Documentation pages (/docs, /pricing, /api, /README) all returned only a 'Connect wallet' prompt with no substantive content.
- —The endpoint path '/api/resource/22' does not match any of the advertised API paths on the landing page (which use /api/v1/ and /api/v2/ prefixes), so its purpose is unclear.
Citations
- —Endpoint returns a valid x402 challenge with maxAmountRequired of 20000 base units in USDC on Basehttps://lowpaymentfee.com/api/resource/22
- —USDC asset contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/resource/22
- —All listed endpoints priced at $0.02 per request with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —Platform advertises endpoints across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com