x402basequality 0.35

Pay-per-call API platform on Base (USDC) via x402 — $0.02/request, no API keys required.

Price
0.02 USDC / call
Protocol
x402
Verified
no
Endpoint
https://lowpaymentfee.com/api/v1/payments/235

What it does

lowpaymentfee.com is an x402-enabled API platform that offers a broad collection of endpoints spanning data analytics, AI/ML inference, finance/Web3 data, and utility services. Every endpoint costs $0.02 per request, paid in USDC on the Base network. There are no API keys, no rate limits, and no signup — callers simply attach an x402 payment header to each request.

The specific endpoint at `/api/v1/payments/235` is listed as "Premium API Access" and accepts POST requests. Its x402 challenge advertises a maxAmountRequired of 20,000 base units of USDC (asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Base), which equals $0.02 given USDC's 6 decimals. The payment scheme is "exact" with a 300-second timeout, settling to address 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3.

The broader platform advertises 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. However, documentation beyond the landing page is essentially empty (all sub-pages just show "Connect wallet"), so the actual request/response schemas for individual endpoints are unknown.

Capabilities

x402-paymentusdc-basepay-per-requestno-api-keydata-analyticsai-inferencesentiment-analysistext-summarizationclassificationembeddingsfinance-datacrypto-datageocodingutility-services

Use cases

  • —Agents that need on-demand AI inference (sentiment, summarization, classification) without managing API keys
  • —Fetching real-time crypto token quotes or gas estimates with per-call micropayments
  • —Geocoding or data validation as a utility service paid per request via x402
  • —Programmatic data export or analytics metrics retrieval settled in USDC on Base

Fit

Best for

  • —Developers or agents wanting zero-signup, pay-as-you-go API access
  • —x402-compatible agents that can attach payment headers automatically
  • —Use cases requiring low-cost ($0.02) per-call pricing with no rate limits

Not for

  • —Users who need detailed API documentation or well-defined request/response schemas before integrating
  • —High-volume consumers who would benefit from bulk pricing or subscription plans
  • —Users without USDC on the Base network

Quick start

curl -X POST https://lowpaymentfee.com/api/v1/payments/235 \
  -H "Content-Type: application/json" \
  -H "X-PAYMENT: <x402-payment-header>" \
  -d '{}'

Endpoint

URLhttps://lowpaymentfee.com/api/v1/payments/235
Transporthttp
Protocolx402
Pay to0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3
CurrencyUSD COIN

Quality

0.35/ 1.00

The x402 challenge is live and well-formed, confirming the endpoint works and pricing is clear ($0.02 USDC on Base). However, there is no OpenAPI schema, no documentation of request/response formats, and all doc/pricing/README pages are empty stubs showing only 'Connect wallet'. The specific purpose of the /payments/235 endpoint beyond 'Premium API Access' is unknown.

Warnings

  • —All documentation pages (/docs, /api, /pricing, /README) are empty — they only display 'Connect wallet'
  • —No OpenAPI or request/response schema is available for any endpoint
  • —The specific functionality of /api/v1/payments/235 ('Premium API Access') is not documented — it is unclear what it returns
  • —The platform lists many endpoint categories (AI, finance, geo, etc.) but none have documented input/output contracts

Citations

Provenance

Indexed fromx402_bazaar
Enriched2026-04-19 07:00:34Z · anthropic/claude-opus-4.6 · v2
First seen2026-04-18
Last seen2026-04-23

Agent access

JSONhttps://clawmart.sh/api/listings/ktVyG9
Pay-per-call API platform on Base (USDC) via x402 — $0.02/request, no API keys required. — Clawmart · Clawmart