Pay-per-call API platform on Base network via x402 — $0.02/request in USDC.
What it does
lowpaymentfee.com is an x402-enabled API platform that offers a variety of endpoints across data & analytics, AI & machine learning, finance & Web3, and infrastructure utility categories. All endpoints are priced at $0.02 per request, payable in USDC on the Base network with no API keys, rate limits, or commitments required.
The specific endpoint at `/api/v1/transactions/299` is listed as "Premium API Access" and returns a 402 challenge requesting up to 20,000 base units of USDC (0x8335…2913 on Base), which equals $0.02 given USDC's 6 decimals. Payment is via the x402 "exact" scheme with a 300-second timeout. The endpoint accepts POST requests and returns application/json.
The broader platform advertises endpoints for sentiment analysis, text summarization, classification, embeddings, price feeds, exchange rates, token quotes, gas estimates, geocoding, validation, conversion, and data generation. However, documentation pages (docs, pricing, README) all resolve to a minimal "Connect wallet" prompt with no further technical detail, so the actual behavior and response schemas of these endpoints remain undocumented. The specific functionality behind the `/api/v1/transactions/299` path is unclear — the name "Premium API Access" is generic and no input/output schema beyond `application/json` is provided.
Capabilities
Use cases
- —Accessing pay-per-call API services without API key registration
- —Making micropayment-gated HTTP requests settled in USDC on Base
- —Integrating agent-purchasable endpoints into automated workflows
Fit
Best for
- —Developers wanting zero-signup, pay-as-you-go API access
- —AI agents that can settle x402 payments autonomously
- —Users who prefer crypto micropayments over subscription billing
Not for
- —Users needing detailed API documentation or response schemas before purchasing
- —High-volume consumers who would benefit from bulk/subscription pricing
- —Anyone without a Base-network USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transactions/299 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is live and returns a valid x402 402 challenge, but there is no documentation, no input/output schema, and the endpoint name 'Premium API Access' is entirely generic. The docs, pricing, and README pages all render only 'Connect wallet' with no useful content. It is impossible to determine what this specific endpoint actually does without paying for a request.
Warnings
- —No documentation available — all doc pages resolve to a 'Connect wallet' stub
- —The endpoint path '/api/v1/transactions/299' and title 'Premium API Access' are generic; actual functionality is unknown
- —No input or output schema provided beyond mimeType: application/json
- —No OpenAPI spec, no examples, no error documentation
Citations
- —All endpoints priced at $0.02 per request with no API keys, rate limits, or commitmentshttps://lowpaymentfee.com
- —x402 challenge requests maxAmountRequired of 20000 base units of USDC on Base networkhttps://lowpaymentfee.com/api/v1/transactions/299
- —USDC asset address 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/transactions/299
- —Platform lists endpoints across data/analytics, AI/ML, finance/Web3, and infrastructure categorieshttps://lowpaymentfee.com