Pay-per-call premium API access on Base via x402 — $0.02/request in USDC.
What it does
This endpoint at lowpaymentfee.com provides "Premium API Access" via the x402 payment protocol. The site hosts a broad catalog of pay-per-request APIs spanning data & analytics, AI/ML inference (sentiment analysis, 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, settled in USDC on the Base network.
The specific endpoint `/api/v1/payments/86` is labeled "Premium API Access" and returns a valid x402 challenge with a maxAmountRequired of 20,000 base units of USDC (0x8335…2913 on Base, 6 decimals), which equals $0.02. Payment is made via the x402 exact scheme — no API keys, no rate limits, and no subscriptions required. The endpoint accepts POST requests and returns application/json.
Documentation is extremely sparse: the docs, pricing, API, 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 of what this particular endpoint actually returns. The site's landing page lists many endpoints but does not describe what data or functionality `/api/v1/payments/86` specifically provides. Without documentation, it is unclear what request body (if any) is expected or what the response payload looks like.
Capabilities
Use cases
- —Accessing premium API functionality with per-request USDC micropayments on Base
- —Agent-driven API consumption without pre-registration or API keys
- —Programmatic pay-as-you-go access to data, AI, finance, or utility endpoints
Fit
Best for
- —Developers wanting zero-commitment, pay-per-use API access
- —AI agents that can settle x402 payments autonomously
- —Users who prefer crypto micropayments over subscription billing
Not for
- —Users who need detailed API documentation or guaranteed SLAs before purchasing
- —High-volume consumers who would benefit from bulk pricing or subscriptions
- —Users without a Base-compatible USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/payments/86 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is live and returns a valid x402 challenge, confirming it accepts payments. However, there is no OpenAPI spec, no documentation beyond a landing page listing, no request/response examples, and the specific purpose of /api/v1/payments/86 ('Premium API Access') is entirely undefined. The docs/pricing/README pages are empty. This is effectively a stub listing.
Warnings
- —No documentation available — docs, pricing, API, and README pages all show only 'Connect wallet' with no content
- —The specific functionality of /api/v1/payments/86 is undocumented; 'Premium API Access' is a generic label
- —No request body schema or response schema is documented anywhere
- —No OpenAPI or machine-readable spec available
Citations
- —The endpoint returns a valid x402 challenge with maxAmountRequired of 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/payments/86
- —All listed APIs are priced at $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —The site offers APIs across Data & Analytics, AI & Machine Learning, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com
- —The USDC asset address 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 is on Base networkhttps://lowpaymentfee.com/api/v1/payments/86