x402basequality 0.45

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

Price
0.02 USDC / call
Protocol
x402
Verified
no
Endpoint
https://lowpaymentfee.com/api/v1/products/35

What it does

lowpaymentfee.com is an x402-enabled API marketplace offering a variety of endpoints across data analytics, AI/ML inference, finance/Web3, and infrastructure utilities. Every endpoint costs $0.02 per request, paid in USDC on the Base network with no API keys, no rate limits, and no commitments required. The platform uses the x402 payment protocol: callers receive a 402 challenge with payment details, settle in USDC, and get immediate access to the response.

The specific endpoint at `/api/v1/products/35` is listed as "Premium API Access" and returns a 402 challenge requesting up to 20,000 base units of USDC (0x8335…2913 on Base), which equals $0.02 given USDC's 6 decimals. The payment scheme is "exact" with a 300-second timeout. The endpoint accepts POST requests and returns application/json.

The broader platform advertises endpoints for sentiment analysis, text summarization, classification, embeddings, price feeds, exchange rates, token quotes, gas estimates, geocoding, validation, conversion, and data generation — all at the same $0.02 price point. Documentation pages exist but appear to require wallet connection to view, so detailed request/response schemas for individual endpoints are not available from the crawl.

Capabilities

x402-paymentusdc-base-networkpay-per-requestno-api-keyjson-responsepost-method

Use cases

  • —Agents needing on-demand API access without pre-registration or API keys
  • —Programmatic access to analytics, AI inference, or financial data with per-call USDC payments
  • —Testing x402 payment protocol integrations against a live endpoint

Fit

Best for

  • —Developers or agents wanting zero-friction, keyless API access
  • —x402-compatible wallets and agent frameworks on Base
  • —Low-volume or sporadic API consumers who prefer pay-per-use

Not for

  • —High-volume consumers needing bulk pricing or subscription discounts
  • —Users without USDC on the Base network
  • —Applications requiring detailed OpenAPI schemas or extensive documentation

Quick start

# 1. Send POST to the endpoint — receive 402 challenge
curl -X POST https://lowpaymentfee.com/api/v1/products/35
# 2. Parse the 402 JSON for payment details (payTo, asset, maxAmountRequired)
# 3. Sign an x402 payment and include it in the X-PAYMENT header
curl -X POST https://lowpaymentfee.com/api/v1/products/35 \
  -H "X-PAYMENT: <signed-payment-token>"

Example

Response

{
  "error": "X-PAYMENT header is required",
  "accepts": [
    {
      "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
      "extra": {
        "name": "USD Coin",
        "version": "2"
      },
      "payTo": "0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3",
      "scheme": "exact",
      "network": "base",
      "mimeType": "application/json",
      "resource": "https://lowpaymentfee.com/api/v1/products/35",
      "description": "Premium API Access",
      "maxAmountRequired": "20000",
      "maxTimeoutSeconds": 300
    }
  ],
  "x402Version": 1
}

Endpoint

URLhttps://lowpaymentfee.com/api/v1/products/35
Transporthttp
Protocolx402
Pay to0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3
CurrencyUSD COIN

Quality

0.45/ 1.00

The endpoint is live and returns a valid 402 challenge with clear pricing ($0.02 USDC on Base). However, there is no OpenAPI schema, no documentation of request/response payloads for the actual product endpoint, and the docs/pricing/README pages all require wallet connection and yield no useful content. The endpoint name 'Premium API Access' is generic and doesn't describe what data or service is returned after payment.

Warnings

  • —No OpenAPI or schema documentation available — request/response format for the paid endpoint is unknown
  • —Documentation pages require wallet connection and provide no public content
  • —The endpoint name 'Premium API Access' is generic; it is unclear what specific data or service /api/v1/products/35 returns after successful payment
  • —The broader platform lists many endpoints but none have documented schemas

Citations

Provenance

Indexed fromx402_bazaar
Enriched2026-04-18 21:48:03Z · anthropic/claude-opus-4.6 · v2
First seen2026-04-18
Last seen2026-04-23

Agent access

JSONhttps://clawmart.sh/api/listings/TbR9hV
Pay-per-request API platform on Base network via x402 — $0.02/call in USDC. — Clawmart · Clawmart