x402basequality 0.30

x402-gated API platform on Base offering 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/cards/50

What it does

lowpaymentfee.com is an x402-protocol API marketplace that gates access to a variety of endpoints behind per-request micropayments settled in USDC on the Base network. The specific endpoint at `/api/v1/cards/50` is listed as "Premium API Access" and costs up to $0.02 per call (maxAmountRequired of 20,000 base units of USDC, which has 6 decimals = $0.02). No API keys or rate limits are required; callers simply attach an X-PAYMENT header with a valid x402 payment proof.

The broader platform advertises four categories of endpoints: 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.

The `/api/v1/cards/50` endpoint itself lacks detailed documentation — the docs, pricing, and API pages all render only a "Connect wallet" prompt with no further content. There is no OpenAPI schema, no request/response examples, and no description of what "cards/50" actually returns. The endpoint is confirmed live via a valid 402 challenge, but the actual functionality behind this specific path is unclear from available materials.

Capabilities

x402-paymentusdc-baseper-request-micropaymentno-api-keyno-rate-limitpost-endpointjson-response

Use cases

  • —Accessing premium API data with per-call USDC micropayments on Base
  • —Agent-driven API consumption without pre-registration or API keys
  • —Pay-as-you-go access to data, AI, finance, or utility endpoints

Fit

Best for

  • —Developers wanting zero-commitment, pay-per-use API access
  • —AI agents that can settle x402 payments autonomously on Base
  • —Projects needing low-friction API access without subscription overhead

Not for

  • —Users who need detailed API documentation or OpenAPI specs before integrating
  • —High-volume consumers who would benefit from bulk pricing or subscriptions
  • —Anyone unable to transact in USDC on the Base network

Quick start

curl -X POST https://lowpaymentfee.com/api/v1/cards/50 \
  -H "Content-Type: application/json" \
  -H "X-PAYMENT: <x402-payment-proof>"

Endpoint

URLhttps://lowpaymentfee.com/api/v1/cards/50
Transporthttp
Protocolx402
Pay to0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3
CurrencyUSD COIN

Quality

0.30/ 1.00

The endpoint is confirmed live via a valid x402 402 challenge, and pricing is clear ($0.02 USDC on Base). However, there is no documentation for what /api/v1/cards/50 actually does, no request/response schema, no examples, and the docs/pricing/API pages are all empty beyond a wallet-connect prompt. The specific functionality of this endpoint is entirely unknown.

Warnings

  • —No documentation available for /api/v1/cards/50 — the purpose and response format of this endpoint are unknown
  • —All secondary pages (docs, pricing, API, README) render only 'Connect wallet' with no usable content
  • —No OpenAPI schema or request/response examples provided
  • —The endpoint path 'cards/50' does not correspond to any of the advertised API categories on the homepage

Citations

Provenance

Indexed fromx402_bazaar
Enriched2026-04-19 03:00:33Z · anthropic/claude-opus-4.6 · v2
First seen2026-04-18
Last seen2026-04-23

Agent access

JSONhttps://clawmart.sh/api/listings/seEBS3
x402-gated API platform on Base offering data, AI, finance, and utility endpoints at $0.02/request. — Clawmart · Clawmart