x402basequality 0.30

x402-gated premium API endpoint on Base, pay $0.02 per request in USDC.

Price
0.02 USDC / call
Protocol
x402
Verified
no
Endpoint
https://lowpaymentfee.com/api/v1/cards/92

What it does

This endpoint at `/api/v1/cards/92` is part of the lowpaymentfee.com platform, a collection of x402-protocol pay-per-request APIs spanning data analytics, AI/ML inference, finance/Web3, and infrastructure utilities. The specific resource at `/cards/92` is labeled "Premium API Access" but its exact functionality is not documented beyond that label. It is one of many endpoints on the platform, all priced uniformly at $0.02 per call.

Payment is handled via the x402 protocol on the Base network using USDC (contract `0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913`). The challenge advertises a `maxAmountRequired` of 20,000 base units, which at 6 decimals equals $0.02. No API keys or rate limits are required — callers simply attach an `X-PAYMENT` header with a valid x402 payment proof. The endpoint accepts POST requests and returns `application/json`.

The broader platform offers endpoints for sentiment analysis, text summarization, classification, embeddings, price feeds, exchange rates, geocoding, validation, and more — all at the same $0.02/request price point. However, documentation is extremely thin: the docs, API, pricing, and README pages all render only a "Connect wallet" prompt with no further technical detail. There is no OpenAPI spec, no request/response schema, and no usage examples available. The exact purpose and output of `/api/v1/cards/92` specifically is unclear.

Capabilities

x402-paymentusdc-basepay-per-requestjson-responseno-api-keypost-method

Use cases

  • —Accessing a premium API resource with per-request USDC micropayments
  • —Integrating x402-gated endpoints into agent workflows without API key management
  • —Paying for API calls on-chain via the Base L2 network

Fit

Best for

  • —Developers experimenting with x402 pay-per-request protocols
  • —Agents that can settle USDC payments on Base
  • —Use cases requiring keyless, permissionless API access

Not for

  • —Users who need detailed API documentation or request/response schemas before integrating
  • —Applications requiring free or subscription-based API access
  • —Production systems that need guaranteed SLAs or support

Quick start

curl -X POST https://lowpaymentfee.com/api/v1/cards/92 \
  -H "Content-Type: application/json" \
  -H "X-PAYMENT: <x402-payment-proof>"

Endpoint

URLhttps://lowpaymentfee.com/api/v1/cards/92
Transporthttp
Protocolx402
Pay to0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3
CurrencyUSD COIN

Quality

0.30/ 1.00

The endpoint is live and returns a valid x402 402 challenge, confirming it accepts payments. However, there is no documentation, no OpenAPI spec, no request/response schema, and no explanation of what '/api/v1/cards/92' actually returns. The docs pages are empty beyond a wallet connect prompt. This is effectively a stub listing.

Warnings

  • —The specific functionality of /api/v1/cards/92 ('Premium API Access') is completely undocumented — its purpose, expected input, and output are unknown.
  • —No OpenAPI spec, request schema, or response schema is available anywhere on the site.
  • —All documentation pages (docs, API, pricing, README) render only 'Connect wallet' with no technical content.
  • —The platform lists many endpoints but none have detailed documentation visible to crawlers.

Citations

Provenance

Indexed fromx402_bazaar
Enriched2026-04-19 03:08:50Z · anthropic/claude-opus-4.6 · v2
First seen2026-04-18
Last seen2026-04-22

Agent access

JSONhttps://clawmart.sh/api/listings/ZS3nJw
x402-gated premium API endpoint on Base, pay $0.02 per request in USDC. — Clawmart · Clawmart