x402basequality 0.25

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/30

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 `/api/v1/cards/30` is listed as "Premium API Access" and costs $0.02 per call (20,000 base units of USDC with 6 decimals). Payment is handled via the x402 exact scheme — no API keys, accounts, or rate limits are required; callers simply attach an X-PAYMENT header with a valid payment proof.

The broader platform advertises four categories of APIs: 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 uniformly priced at $0.02 per request.

Documentation is extremely sparse — the /docs, /pricing, /api, and /README 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 the `/api/v1/cards/30` endpoint actually returns. The endpoint is confirmed live (returns a proper 402 challenge), but without documentation it is unclear what data or functionality "Premium API Access" provides or what POST body it expects.

Capabilities

x402-paymentusdc-baseper-request-micropaymentno-api-keypost-endpointjson-response

Use cases

  • —Programmatic access to paid API endpoints without account registration
  • —Agent-driven API consumption with per-call USDC micropayments on Base
  • —Exploring x402 protocol integration for pay-as-you-go services

Fit

Best for

  • —Developers experimenting with x402 micropayment protocol
  • —AI agents that need keyless, pay-per-request API access
  • —Users who want to avoid subscriptions and pay only per call

Not for

  • —Production workloads requiring documented, well-specified API contracts
  • —Users who need detailed request/response schemas before integrating
  • —Anyone without a Base-network USDC wallet

Quick start

# The endpoint returns 402 with an x402 challenge.
# Attach a valid X-PAYMENT header (x402 exact scheme, USDC on Base) to pay $0.02.
curl -X POST https://lowpaymentfee.com/api/v1/cards/30 \
  -H "Content-Type: application/json" \
  -H "X-PAYMENT: <x402-payment-proof>"

Endpoint

URLhttps://lowpaymentfee.com/api/v1/cards/30
Transporthttp
Protocolx402
Pay to0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3
CurrencyUSD COIN

Quality

0.25/ 1.00

The endpoint is live and returns a valid x402 402 challenge, confirming it exists and accepts USDC on Base. However, there is no OpenAPI schema, no documentation beyond a landing page listing, no request/response examples, and no explanation of what 'Premium API Access' at /api/v1/cards/30 actually returns. This is effectively a stub listing.

Warnings

  • —No documentation available — /docs, /pricing, /api, and /README all render only 'Connect wallet' with no content.
  • —No OpenAPI or schema provided; request body format and response structure are completely unknown.
  • —The purpose of the specific endpoint /api/v1/cards/30 ('Premium API Access') is undocumented and unclear.
  • —The platform lists many endpoint categories (AI, finance, data, infra) but provides no evidence any of them return real data.

Citations

Provenance

Indexed fromx402_bazaar
Enriched2026-04-19 02:53:40Z · anthropic/claude-opus-4.6 · v2
First seen2026-04-18
Last seen2026-04-22

Agent access

JSONhttps://clawmart.sh/api/listings/h8YQ2y
x402-gated API platform on Base offering data, AI, finance, and utility endpoints at $0.02/request. — Clawmart · Clawmart