x402basequality 0.30

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

Price
0.02 USDC / call
Protocol
x402
Verified
no
Endpoint
https://lowpaymentfee.com/api/v1/inbox/4

What it does

lowpaymentfee.com is an x402-enabled API platform that offers a broad catalog of pay-per-request endpoints settled in USDC on the Base network. The specific endpoint `/api/v1/inbox/4` is listed as "Premium API Access" and costs up to $0.02 per call (20,000 base units of USDC with 6 decimals). Payment is handled via the x402 protocol — no API keys, no subscriptions, no rate limits. You send a POST request with an X-PAYMENT header containing a signed USDC payment, and the endpoint returns its result.

The broader platform advertises four endpoint families: 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 are priced at $0.02 per request and settle on Base.

However, the specific functionality of `/api/v1/inbox/4` is unclear. The description is simply "Premium API Access" with no further documentation, no OpenAPI schema, and no example request/response. The crawled docs pages (`/api`, `/pricing`, `/README`) all returned only a "Connect wallet" prompt with no additional content. Without documentation or schema details, it is impossible to confirm what this particular endpoint actually does or what input it expects beyond a POST with JSON content type.

Capabilities

x402-paymentusdc-settlementbase-networkpay-per-requestno-api-keyjson-api

Use cases

  • —Programmatic access to a pay-per-call API without needing API keys or subscriptions
  • —Agent-driven workflows that need on-demand API access settled in USDC on Base
  • —Testing x402 protocol integrations with a low-cost endpoint

Fit

Best for

  • —Developers or agents wanting zero-signup, pay-as-you-go API access
  • —x402 protocol experimentation at low cost ($0.02/call)
  • —Crypto-native applications that prefer on-chain settlement

Not for

  • —Users who need detailed API documentation or guaranteed SLAs before integrating
  • —High-volume use cases where per-request pricing may add up compared to subscription models
  • —Anyone without USDC on Base network

Quick start

curl -X POST https://lowpaymentfee.com/api/v1/inbox/4 \
  -H "Content-Type: application/json" \
  -H "X-PAYMENT: <x402-payment-header>" \
  -d '{}'

Endpoint

URLhttps://lowpaymentfee.com/api/v1/inbox/4
Transporthttp
Protocolx402
Pay to0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3
CurrencyUSD COIN

Quality

0.30/ 1.00

The endpoint is live (returns a valid 402 x402 challenge) and pricing is clear ($0.02 USDC on Base), but there is no documentation, no OpenAPI schema, no example requests or responses, and the purpose of /api/v1/inbox/4 specifically is undocumented. The crawled pages beyond the landing page returned no useful content.

Warnings

  • —No OpenAPI or schema documentation available for this endpoint
  • —The specific function of /api/v1/inbox/4 is unknown — 'Premium API Access' is the only description
  • —All doc pages (/api, /pricing, /README) returned only 'Connect wallet' with no content
  • —No example request or response available to verify endpoint behavior

Citations

Provenance

Indexed fromx402_bazaar
Enriched2026-04-21 21:46:51Z · anthropic/claude-opus-4.6 · v2
First seen2026-04-21
Last seen2026-04-21

Agent access

JSONhttps://clawmart.sh/api/listings/uHGcdb
Pay-per-call API platform on Base (USDC) covering data, AI, finance, and utility endpoints at $0.02/request. — Clawmart · Clawmart