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 set of endpoints across four categories: Data & Analytics (metrics, reports, data 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 `/api/v1/messages/30` is listed as "Premium API Access." Its x402 challenge advertises a maxAmountRequired of 20,000 base units of USDC (0x8335… 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 sign-up required — callers simply attach an X-PAYMENT header to each POST request.

Documentation is minimal: the landing page lists available endpoints and pricing, but the /api, /pricing, and /README pages all resolve to a wallet-connect stub with no further detail. There is no OpenAPI spec, no request/response schema documentation, and no usage examples. The purpose of the `/api/v1/messages/30` endpoint specifically is unclear — it could be a messaging or content retrieval endpoint, but no description beyond "Premium API Access" is provided.

Capabilities

x402-paymentusdc-basepay-per-requestdata-analyticsai-sentimentai-summarizationai-classificationai-embeddingsfinance-pricesexchange-ratescrypto-gasgeocodingvalidationconversion

Use cases

  • Accessing AI inference endpoints (sentiment, summarization, classification, embeddings) without API keys
  • Fetching real-time financial data such as token quotes, exchange rates, and gas estimates
  • Running utility operations like geocoding, validation, and data conversion on a per-call basis
  • Integrating pay-per-request data analytics into agent workflows

Fit

Best for

  • Agents needing low-cost, no-signup API access settled in USDC on Base
  • Developers prototyping with multiple lightweight API categories under one provider
  • Workflows requiring micropayment-gated endpoints without rate limits

Not for

  • Users who need detailed API documentation or OpenAPI specs before integrating
  • High-volume production workloads where per-request crypto settlement adds overhead
  • Anyone without a Base-compatible USDC wallet

Quick start

curl -X POST https://lowpaymentfee.com/api/v1/messages/30 \
  -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 spec, no request/response schema, no documentation beyond a landing page listing, and the specific purpose of /api/v1/messages/30 is undocumented. Effectively a stub listing.

Warnings

  • No OpenAPI or schema documentation available for any endpoint
  • The specific endpoint /api/v1/messages/30 has no description beyond 'Premium API Access' — its function is unknown
  • The /api, /pricing, and /README pages all return only a wallet-connect stub with no content
  • No request or response examples are available anywhere in the crawled material

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/30 specifies maxAmountRequired of 20000 base units of USDC (asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Base
    https://lowpaymentfee.com/api/v1/messages/30
  • Available API categories include Data & Analytics, AI & Machine Learning, Finance & Web3, and Infrastructure
    https://lowpaymentfee.com

Provenance

Indexed fromx402_bazaar
Enriched2026-04-21 23:08:56Z · anthropic/claude-opus-4.6 · v2
First seen2026-04-21
Last seen2026-04-22

Agent access