x402basequality 0.35

Pay-per-call premium API endpoint on Base via x402, settled in USDC.

Price
0.02 USDC / call
Protocol
x402
Verified
no
Endpoint
https://lowpaymentfee.com/api/endpoint-20

What it does

lowpaymentfee.com hosts a collection of pay-per-request API endpoints accessible via the x402 payment protocol on the Base network. This specific endpoint (`/api/endpoint-20`) is labeled "Premium API Access" and accepts POST requests. Payment is settled in USDC (USD Coin) on Base, with a maximum amount of 20,000 base units — equivalent to $0.02 per request (USDC uses 6 decimals). No API keys, rate limits, or upfront commitments are required; callers simply attach an X-PAYMENT header to each request.

The broader lowpaymentfee.com platform advertises endpoints across several categories: 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 listed endpoints share the same $0.02/request pricing. However, this particular endpoint (`/api/endpoint-20`) does not clearly map to any of those named services — it may be a generic or demonstration endpoint.

The endpoint is live and returns a valid x402 challenge (HTTP 402) with version 1 of the protocol. The payment address is `0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3`, and the USDC contract on Base is `0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913`. The response MIME type is `application/json`. Documentation beyond the landing page is essentially empty (all sub-pages just show "Connect wallet"), so the exact request/response schema for this endpoint is unknown.

Capabilities

x402-paymentusdc-settlementbase-networkpay-per-requestjson-responseno-api-keypost-method

Use cases

  • —Agent-driven API consumption where per-call USDC micropayments replace traditional API keys
  • —Programmatic access to a premium endpoint without subscription or rate-limit overhead
  • —Demonstrating x402 payment protocol integration on the Base L2 network

Fit

Best for

  • —Developers experimenting with x402 payment-gated APIs
  • —AI agents that can settle USDC micropayments on Base
  • —Projects needing keyless, pay-as-you-go API access

Not for

  • —Users who need detailed API documentation or well-defined request/response schemas
  • —High-volume consumers who prefer flat-rate or subscription pricing
  • —Anyone without a Base-compatible USDC wallet

Quick start

curl -X POST https://lowpaymentfee.com/api/endpoint-20 \
  -H "Content-Type: application/json" \
  -H "X-PAYMENT: <x402-payment-token>"

Endpoint

URLhttps://lowpaymentfee.com/api/endpoint-20
Transporthttp
Protocolx402
Pay to0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3
CurrencyUSD COIN

Quality

0.35/ 1.00

The endpoint is live and returns a valid x402 challenge, but there is no documentation, no OpenAPI schema, no request/response examples, and the endpoint path (/api/endpoint-20) doesn't correspond to any named service on the site. All doc pages return only 'Connect wallet' with no useful content.

Warnings

  • —No documentation available — all doc/pricing/README pages render only 'Connect wallet'
  • —The endpoint path /api/endpoint-20 does not match any of the named API routes listed on the landing page; its actual functionality is unknown
  • —No request body schema or response schema is documented anywhere
  • —No OpenAPI spec or AI plugin manifest found

Citations

Provenance

Indexed fromx402_bazaar
Enriched2026-04-18 20:21:59Z · anthropic/claude-opus-4.6 · v2
First seen2026-04-18
Last seen2026-04-23

Agent access

JSONhttps://clawmart.sh/api/listings/Tb4cXs
Pay-per-call premium API endpoint on Base via x402, settled in USDC. — Clawmart · Clawmart