x402basequality 0.30

Pay-per-call API platform on Base network — $0.02/request via x402 USDC payments.

Price
0.02 USDC / call
Protocol
x402
Verified
no
Endpoint
https://lowpaymentfee.com/api/v1/inbox/14

What it does

lowpaymentfee.com is a pay-per-request API platform that uses the x402 protocol to accept USDC payments on the Base network. The specific endpoint `/api/v1/inbox/14` is listed as "Premium API Access" and accepts POST requests with payment settled in USDC (contract 0x8335…2913 on Base). The maximum amount required per call is 20,000 base units of USDC, which equals $0.02 (USDC uses 6 decimals). No API keys, rate limits, or upfront commitments are required — callers simply attach an X-PAYMENT header with a valid x402 payment proof.

The broader platform advertises multiple API categories including 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 listed at the same $0.02/request price point.

However, the specific functionality behind `/api/v1/inbox/14` is not documented. The endpoint path suggests a mailbox or inbox resource (item #14), but no schema, example payloads, or response formats are provided. The crawled pages beyond the landing page returned only "Connect wallet" prompts with no additional documentation. Without knowing what this endpoint actually returns, callers should treat it as an opaque premium resource until further documentation is available.

Capabilities

x402-paymentusdc-settlementbase-networkpay-per-requestno-api-keypost-endpoint

Use cases

  • —Accessing a premium inbox/resource endpoint with per-request USDC micropayments
  • —Integrating pay-as-you-go API calls without managing API keys or subscriptions
  • —Agent-driven workflows that need on-demand paid API access on Base

Fit

Best for

  • —Developers who want zero-commitment, pay-per-use API access
  • —AI agents with x402-compatible payment capabilities on Base
  • —Users who prefer crypto-native micropayments over traditional billing

Not for

  • —Users who need detailed API documentation and response schemas before integrating
  • —High-volume callers who would benefit from bulk pricing or subscriptions
  • —Developers who cannot transact in USDC on the Base network

Quick start

curl -X POST https://lowpaymentfee.com/api/v1/inbox/14 \
  -H "Content-Type: application/json" \
  -H "X-PAYMENT: <x402-payment-proof>"

Endpoint

URLhttps://lowpaymentfee.com/api/v1/inbox/14
Transporthttp
Protocolx402
Pay to0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3
CurrencyUSD COIN

Quality

0.30/ 1.00

The endpoint is live (402 challenge confirmed) and pricing is clear ($0.02 USDC on Base), but there is no documentation for what /api/v1/inbox/14 actually does, no request/response schema, and no examples. The crawled docs pages returned only wallet-connect prompts. This is effectively a stub listing.

Warnings

  • —The specific functionality of /api/v1/inbox/14 is completely undocumented — the endpoint name 'Premium API Access' is generic and uninformative.
  • —No request body schema or response schema is available; callers cannot know what to send or what to expect.
  • —Documentation pages (/api, /pricing, /README) all returned only 'Connect wallet' with no useful content.
  • —The platform lists many API categories on its landing page, but it is unclear whether all endpoints are actually functional.

Citations

Provenance

Indexed fromx402_bazaar
Enriched2026-04-21 21:34:06Z · anthropic/claude-opus-4.6 · v2
First seen2026-04-21
Last seen2026-04-22

Agent access

JSONhttps://clawmart.sh/api/listings/6pejtN
Pay-per-call API platform on Base network — $0.02/request via x402 USDC payments. — Clawmart · Clawmart