x402basequality 0.35

Pay-per-call API platform on Base via x402 — $0.02/request, no API keys required.

Price
0.02 USDC / call
Protocol
x402
Verified
no
Endpoint
https://lowpaymentfee.com/api/v1/transactions/339

What it does

lowpaymentfee.com is an x402-enabled API platform that offers a broad catalog of endpoints spanning data analytics, AI/ML inference, finance/Web3 data, and infrastructure utilities. Every endpoint is priced at $0.02 per request, paid in USDC on the Base network via the x402 payment protocol. There are no API keys, no rate limits, and no subscription commitments — callers simply attach an X-PAYMENT header with a valid x402 payment proof to access any endpoint.

The specific endpoint at `/api/v1/transactions/339` is listed as "Premium API Access" and accepts POST requests. Its x402 challenge advertises a maxAmountRequired of 20000 base units of USDC (0x8335…2913 on Base), which equals $0.02 given USDC's 6 decimals. The broader platform lists 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 is extremely sparse: 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 documentation, and no usage examples available from the crawled content. The endpoint is confirmed live (returns 402 with a valid x402 challenge), but without documentation it is unclear what request body this particular endpoint expects or what response it returns.

Capabilities

x402-paymentusdc-basepay-per-requestno-api-keypost-endpointjson-response

Use cases

  • —Accessing premium API data with per-request USDC micropayments on Base
  • —Agent-driven API consumption without pre-registration or API key management
  • —Pay-as-you-go access to analytics, AI inference, or financial data endpoints

Fit

Best for

  • —Developers or agents wanting zero-signup, pay-per-call API access
  • —x402-compatible agents that can settle USDC on Base
  • —Low-volume or sporadic API consumers who prefer no subscriptions

Not for

  • —Users needing detailed API documentation or OpenAPI specs before integrating
  • —High-volume consumers who need bulk pricing or rate-limit guarantees
  • —Users who cannot transact in USDC on the Base network

Quick start

curl -X POST https://lowpaymentfee.com/api/v1/transactions/339 \
  -H "Content-Type: application/json" \
  -H "X-PAYMENT: <x402-payment-proof>" \
  -d '{}'

Endpoint

URLhttps://lowpaymentfee.com/api/v1/transactions/339
Transporthttp
Protocolx402
Pay to0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3
CurrencyUSD COIN

Quality

0.35/ 1.00

The endpoint is confirmed live with a valid x402 402 challenge, and the landing page lists pricing and endpoint categories. However, there is no OpenAPI spec, no request/response schema, no documentation beyond a wallet-connect prompt, and no examples. The specific endpoint's purpose ('Premium API Access') is vague with no further detail available.

Warnings

  • —No OpenAPI spec or machine-readable schema available
  • —Documentation pages (/docs, /pricing, /api, /README) all render only 'Connect wallet' with no content
  • —The specific endpoint /api/v1/transactions/339 has no documented request body or response format
  • —Purpose of 'Premium API Access' is unclear — no description beyond the title

Citations

Provenance

Indexed fromx402_bazaar
Enriched2026-04-19 13:05:34Z · anthropic/claude-opus-4.6 · v2
First seen2026-04-18
Last seen2026-04-22

Agent access

JSONhttps://clawmart.sh/api/listings/LxfQpa
Pay-per-call API platform on Base via x402 — $0.02/request, no API keys required. — Clawmart · Clawmart