x402-gated premium API access on Base, pay $0.02 per request in USDC — no API keys required.
What it does
lowpaymentfee.com is an x402-enabled API platform offering a broad catalog of pay-per-request endpoints across data analytics, AI/ML inference, finance/Web3, and infrastructure utilities. All endpoints are gated via the x402 protocol on the Base network, accepting USDC payments with no API keys, no rate limits, and no upfront commitments.
The specific endpoint at `/api/v1/charges/281` is listed as "Premium API Access" and accepts POST requests. The x402 challenge advertises a maximum cost of 20,000 base units of USDC (0x8335…2913 on Base), which equals $0.02 per request (USDC uses 6 decimals). Payment is made via the `exact` scheme with a 300-second timeout. The response MIME type is `application/json`.
The broader platform advertises additional endpoints for sentiment analysis, text summarization, classification, embeddings, price feeds, exchange rates, token quotes, gas estimates, geocoding, validation, conversion, and generation — all at the same $0.02/request price point. However, the crawled documentation pages (docs, pricing, API reference) returned only a wallet-connect prompt with no substantive content, so detailed schemas, request/response examples, and endpoint-specific documentation are unavailable.
Capabilities
Use cases
- —Agents that need on-demand API access without pre-registration or API key management
- —Pay-per-call access to analytics, AI inference, or financial data endpoints
- —Programmatic USDC micropayments for utility services like geocoding or data conversion
- —Web3-native applications consuming real-time price feeds or gas estimates
Fit
Best for
- —AI agents and bots that can settle x402 payments autonomously
- —Developers wanting zero-commitment, pay-as-you-go API access on Base
- —Use cases requiring low-cost ($0.02) per-request billing without subscriptions
Not for
- —Users who need detailed API documentation or OpenAPI schemas before integrating
- —High-volume consumers who would benefit from bulk pricing or subscription plans
- —Users without a Base-compatible USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/charges/281 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"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 examples, and all documentation pages returned only a wallet-connect stub. The purpose of this specific '/charges/281' endpoint beyond 'Premium API Access' is unclear, making this effectively a stub listing.
Warnings
- —No OpenAPI or schema documentation available — all doc pages returned only a wallet-connect prompt
- —The specific functionality of /api/v1/charges/281 ('Premium API Access') is not described anywhere; it is unclear what data or service it provides
- —No request body schema or response examples are documented
- —The broader site lists many endpoints but none have detailed documentation visible in the crawl
Citations
- —The endpoint returns a 402 x402 challenge with maxAmountRequired of 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/charges/281
- —All endpoints are priced at $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —The platform offers endpoints across Data & Analytics, AI & Machine Learning, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com
- —USDC contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/charges/281