Pay-per-call API suite on Base (USDC) covering data, AI, finance, and utilities 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. No API keys, accounts, or rate limits are required — callers simply attach an x402 payment header to each request.
The specific endpoint at `/api/v1/messages/171` is listed as "Premium API Access." Its x402 challenge advertises a maximum cost of 20,000 base units of USDC (0x8335…2913 on Base), which equals $0.02 given USDC's 6 decimals. The endpoint accepts HTTP POST and returns `application/json`. Payment is sent to `0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3` with a 300-second timeout.
The broader platform advertises sibling 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 beyond the landing page is sparse: the /api, /pricing, and /README pages all resolve to a "Connect wallet" prompt with no further detail. Without OpenAPI specs or example request/response payloads, the exact input parameters and output formats for this endpoint remain unknown.
Capabilities
Use cases
- —Agents that need on-demand API access without pre-registration or API keys
- —Micropayment-gated data retrieval where per-call billing is preferred over subscriptions
- —Programmatic access to a variety of utility, AI, and finance endpoints via a single payment protocol
Fit
Best for
- —Developers or agents wanting frictionless, key-less API access settled on Base
- —Low-volume or bursty workloads where $0.02/call flat pricing is economical
- —x402-native agent workflows that already handle on-chain USDC payments
Not for
- —High-volume production workloads needing documented SLAs and guaranteed uptime
- —Use cases requiring detailed API documentation, SDKs, or typed schemas
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/messages/171 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402_payment_header>" \
-d '{}'Endpoint
Quality
The endpoint is live (402 challenge captured) and pricing is clear ($0.02 USDC on Base). However, there is no OpenAPI spec, no request/response examples, and the /api, /pricing, and /README pages are all blank beyond a wallet-connect prompt. The purpose of the specific '/messages/171' path is undocumented, making this effectively a stub listing.
Warnings
- —No OpenAPI or schema documentation available — input parameters and response format are unknown.
- —The specific endpoint path '/api/v1/messages/171' is not explained anywhere on the site; its function is unclear.
- —All documentation pages (/api, /pricing, /README) return only a 'Connect wallet' prompt with no content.
- —The platform lists many endpoint categories but none have published specs or examples.
Citations
- —The endpoint returns a 402 challenge with maxAmountRequired of 20000 base units of USDC on Base networkhttps://lowpaymentfee.com/api/v1/messages/171
- —USDC asset contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/messages/171
- —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 & ML, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com