x402-gated premium API access on Base, pay $0.02 per request in USDC.
What it does
This endpoint at lowpaymentfee.com provides "Premium API Access" behind an x402 paywall on the Base network. The provider operates a suite of pay-per-request APIs spanning data & analytics, 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, settled in USDC on Base with no API keys, no rate limits, and no commitments required.
The specific endpoint `/api/v1/charges/339` is labeled "Premium API Access" in the x402 challenge and accepts POST requests. The challenge advertises a maxAmountRequired of 20,000 base units of USDC (0x8335…2913 on Base), which equals $0.02 given USDC's 6 decimals. Payment is made via the x402 exact scheme with a 300-second timeout. The response MIME type is 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 available. It is unclear what specific data or functionality this particular charges/339 endpoint returns, as the provider's landing page lists many different API categories but does not map charge IDs to specific services.
Capabilities
Use cases
- —Accessing pay-per-request API services without traditional API key registration
- —Making micropayments in USDC on Base for on-demand data or utility endpoints
- —Integrating x402-compatible agents with low-cost API calls
Fit
Best for
- —Developers wanting keyless, pay-as-you-go API access
- —AI agents with x402 payment capability on Base
- —Users who prefer crypto micropayments over subscription billing
Not for
- —Users needing detailed API documentation or OpenAPI specs before integration
- —High-volume use cases where per-request pricing may add up without bulk discounts
- —Users without USDC on Base network
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/charges/339 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is live and returns a valid x402 challenge, but documentation is essentially nonexistent — all doc pages show only 'Connect wallet'. There is no OpenAPI spec, no request/response schema, no examples, and no clarity on what this specific charges/339 endpoint actually returns. The listing is effectively a stub.
Warnings
- —No documentation available — /docs, /pricing, /api, and /README pages all render only 'Connect wallet'
- —No OpenAPI or schema definition found
- —It is unclear what data or service the /api/v1/charges/339 endpoint specifically provides
- —No request body schema or response schema documented
Citations
- —The x402 challenge advertises maxAmountRequired of 20000 base units of USDC (asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Base networkhttps://lowpaymentfee.com/api/v1/charges/339
- —All listed endpoints are priced at $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —The provider offers APIs across Data & Analytics, AI & Machine Learning, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com