x402-payable API platform on Base offering data, AI, finance, and utility endpoints at $0.02/request.
What it does
lowpaymentfee.com is an x402-enabled API marketplace that exposes a broad set of 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 endpoints are priced at $0.02 per request, payable in USDC on the Base network via the x402 protocol — no API keys, no rate limits, and no upfront commitments.
The specific endpoint at `/api/v1/generate/resource/146` is listed as "Premium API Access" and returns a standard x402 challenge with a maxAmountRequired of 20,000 base units of USDC (0.02 USDC, i.e., $0.02). Payment is settled on-chain to address `0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3` using the "exact" payment scheme. The endpoint accepts HTTP POST requests and returns `application/json`.
Documentation beyond the landing page is extremely sparse — the /docs, /api, /pricing, and /README pages all render only a "Connect wallet" prompt with no additional technical detail. There is no OpenAPI spec, no request/response schema documentation, and no example payloads available. The actual functionality behind "Premium API Access" at resource/146 is unclear; it does not map to any of the named endpoints on the homepage. Agents should treat this as a live but under-documented endpoint.
Capabilities
Use cases
- —Programmatic access to utility or generation endpoints without API key management
- —Agent-driven workflows that need on-demand paid API calls settled in USDC on Base
- —Exploring x402 protocol integration for pay-per-request microservices
Fit
Best for
- —Developers experimenting with x402 payment protocol
- —Agents needing keyless, pay-per-call API access on Base
- —Low-volume consumers who want no subscription or minimum commitment
Not for
- —Users who need detailed API documentation or guaranteed SLAs before integrating
- —High-volume production workloads requiring predictable bulk pricing
- —Users without USDC on the Base network
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/generate/resource/146
# Returns 402 with x402 challenge. Include X-PAYMENT header with a signed USDC payment on Base to access.Example
Response
{
"error": "X-PAYMENT header is required",
"accepts": [
{
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"payTo": "0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3",
"scheme": "exact",
"network": "base",
"mimeType": "application/json",
"description": "Premium API Access",
"maxAmountRequired": "20000",
"maxTimeoutSeconds": 300
}
],
"x402Version": 1
}Endpoint
Quality
The endpoint is live and returns a valid x402 challenge, but there is no documentation, no OpenAPI spec, no request/response schema, and no examples. The specific resource/146 path doesn't correspond to any named endpoint on the homepage. Effectively a stub listing.
Warnings
- —No documentation available — /docs, /pricing, /api, and /README pages all render only 'Connect wallet' with no content.
- —No OpenAPI or schema provided; request body format and response structure are unknown.
- —The endpoint path /api/v1/generate/resource/146 ('Premium API Access') does not match any of the named endpoints listed on the homepage — its actual functionality is unclear.
- —Cannot verify what this endpoint actually returns upon successful payment.
Citations
- —All endpoints priced at $0.02/request with no API keys, no rate limits, on Base networkhttps://lowpaymentfee.com
- —x402 challenge returns maxAmountRequired of 20000 base units USDC (= $0.02) on Basehttps://lowpaymentfee.com/api/v1/generate/resource/146
- —Available API categories include Data & Analytics, AI & ML, Finance & Web3, and Infrastructurehttps://lowpaymentfee.com
- —USDC asset contract on Base: 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/generate/resource/146