Pay-per-call API suite on Base (USDC) covering data, AI, finance, and utility endpoints at $0.02/request.
What it does
lowpaymentfee.com is an x402-enabled API platform that offers a broad collection of endpoints spanning data & analytics, AI & machine learning, finance & Web3, and infrastructure utilities. Every endpoint is priced at $0.02 per request, settled in USDC on the Base network. There are no API keys, no rate limits, and no minimum commitments — callers simply attach an x402 payment header to each request.
The specific endpoint at `/api/v1/messages/190` is listed as "Premium API Access." Its x402 challenge advertises a maximum cost of 20,000 base units of USDC (asset 0x8335…2913 on Base), which equals $0.02 given USDC's 6 decimals. The endpoint accepts HTTP POST and returns `application/json`. The broader platform also exposes 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 price point.
Documentation is minimal: the landing page lists available endpoints with short labels and prices, but there is no OpenAPI spec, no request/response schema documentation, and no usage examples. The `/api`, `/pricing`, and `/README` pages all resolve to a bare "Connect wallet" prompt with no additional content. Because of this, the actual input parameters and response shapes for `/api/v1/messages/190` (and the other endpoints) are unknown and must be discovered experimentally.
Capabilities
Use cases
- —Accessing miscellaneous API services with per-call USDC micropayments on Base
- —Agent-driven workflows that need keyless, on-demand API access
- —Experimenting with x402 payment protocol integrations
Fit
Best for
- —Developers exploring x402 pay-per-call patterns
- —Agents that need instant, keyless API access settled in USDC on Base
- —Low-volume or sporadic API consumers who want no subscriptions
Not for
- —Users who need detailed API documentation or OpenAPI specs before integrating
- —High-throughput production workloads where $0.02/request adds up significantly
- —Anyone without a Base-compatible USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/messages/190 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>" \
-d '{}'Endpoint
Quality
The endpoint is live (402 challenge confirmed) and pricing is clear ($0.02 USDC on Base), but there is no OpenAPI spec, no request/response schema, no documentation beyond endpoint names, and the purpose of /api/v1/messages/190 specifically is entirely opaque. This is effectively a stub listing.
Warnings
- —No OpenAPI spec or schema documentation available for any endpoint
- —The specific purpose and expected input/output of /api/v1/messages/190 is unknown
- —All documentation pages (/api, /pricing, /README) return only a 'Connect wallet' prompt with no content
- —Request and response formats must be discovered experimentally
Citations
- —The platform lists endpoints across data, AI, finance, and utility categories all priced at $0.02/requesthttps://lowpaymentfee.com
- —No API keys, no rate limits, instant access, Base networkhttps://lowpaymentfee.com
- —x402 challenge returns maxAmountRequired of 20000 base units of USDC (0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Basehttps://lowpaymentfee.com/api/v1/messages/190