x402basequality 0.35

Pay-per-call API platform on Base (USDC) offering data, AI, finance, and utility endpoints at $0.02/request.

Price
0.02 USDC / call
Protocol
x402
Verified
no

What it does

lowpaymentfee.com is an x402-enabled API platform that exposes a broad catalog of endpoints across four categories: Data & Analytics (metrics, reports, export, insights), AI & Machine Learning (sentiment analysis, text summarization, classification, embeddings), Finance & Web3 (price feeds, exchange rates, token quotes, gas estimates), and Infrastructure utilities (geocoding, validation, conversion, generation). All endpoints are priced at $0.02 per request, settled in USDC on the Base network via the x402 protocol.

The specific endpoint at `/api/v1/messages/120` is listed as "Premium API Access." Its x402 challenge advertises a maxAmountRequired of 20,000 base units of USDC (0x8335…2913 on Base), which equals $0.02 given USDC's 6 decimals. Payment is made via the x402 exact scheme with no API keys, no rate limits, and no upfront commitments required. The endpoint accepts HTTP POST requests and returns application/json.

Note that the `/api/v1/messages/120` endpoint does not clearly map to any of the four advertised categories on the landing page, and no documentation, OpenAPI schema, or usage examples are available. The crawled /api, /pricing, and /README pages all returned only a "Connect wallet" prompt with no substantive content. The actual request/response format for this specific endpoint is unknown.

Capabilities

x402-paymentusdc-basepay-per-requestdata-analyticsai-inferencesentiment-analysistext-summarizationclassificationembeddingsfinance-datageocodingutility-apis

Use cases

  • Accessing AI inference (sentiment, summarization, classification, embeddings) on a per-call basis without API keys
  • Fetching real-time financial data such as token quotes, exchange rates, and gas estimates
  • Running data analytics queries (metrics, reports, insights) with micropayment settlement
  • Geocoding, validation, and data conversion via utility endpoints

Fit

Best for

  • Developers wanting zero-commitment, pay-as-you-go API access
  • AI agents that can settle x402 payments in USDC on Base
  • Projects needing low-cost micropayment-gated endpoints without subscription overhead

Not for

  • Users who need detailed API documentation or OpenAPI schemas before integrating
  • Applications requiring high-throughput bulk access with negotiated pricing
  • Users without USDC on Base or an x402-compatible payment client

Quick start

curl -X POST https://lowpaymentfee.com/api/v1/messages/120 \
  -H "Content-Type: application/json" \
  -H "X-PAYMENT: <x402-payment-header>" \
  -d '{}'

Endpoint

Transporthttp
Protocolx402
Pay to0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3
CurrencyUSD COIN

Quality

0.35/ 1.00

The endpoint is live (402 challenge confirmed) and pricing is clear ($0.02 USDC on Base), but there is no OpenAPI schema, no documentation, no request/response examples, and the /api, /pricing, and /README pages are empty. The specific endpoint path (/api/v1/messages/120) doesn't match any documented category, making its purpose unclear.

Warnings

  • No OpenAPI or schema documentation available for any endpoint
  • The /api/v1/messages/120 path does not correspond to any of the categories listed on the landing page — its actual functionality is unknown
  • The /api, /pricing, and /README pages returned no useful content (only 'Connect wallet')
  • No request body schema or response examples are available anywhere in the crawl

Citations

  • All endpoints are priced at $0.02 per request with no API keys, no rate limits, and instant access on Base network
    https://lowpaymentfee.com
  • The x402 challenge for /api/v1/messages/120 specifies maxAmountRequired of 20000 base units of USDC (asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Base
    https://lowpaymentfee.com/api/v1/messages/120
  • Available API categories include Data & Analytics, AI & Machine Learning, Finance & Web3, and Infrastructure
    https://lowpaymentfee.com

Provenance

Indexed fromx402_bazaar
Enriched2026-04-21 22:49:06Z · anthropic/claude-opus-4.6 · v2
First seen2026-04-21
Last seen2026-04-22

Agent access