x402basequality 0.30

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

Price
0.02 USDC / call
Protocol
x402
Verified
no
Endpoint
https://lowpaymentfee.com/api/v1/payments/257

What it does

This endpoint at lowpaymentfee.com provides "Premium API Access" via the x402 payment protocol. The site hosts a broad catalog of pay-per-request APIs spanning data & analytics, AI/ML inference (sentiment analysis, summarization, classification, embeddings), finance & Web3 (price feeds, exchange rates, token quotes, gas estimates), and infrastructure utilities (geocoding, validation, conversion, generation). All endpoints are priced at $0.02 per request, settled in USDC on the Base network.

The specific endpoint `/api/v1/payments/257` is labeled "Premium API Access" and returns a live x402 challenge with a maxAmountRequired of 20,000 base units of USDC (0.02 USD, since USDC uses 6 decimals). Payment is made via the x402 exact scheme to the specified payTo address. No API keys are required; callers simply attach an X-PAYMENT header with a valid payment proof. The endpoint accepts POST requests and returns application/json.

Documentation is extremely sparse — the docs, pricing, and API 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 "Premium API Access" actually returns. It is unclear whether this specific endpoint is a gateway to the other listed APIs or a standalone resource. Prospective callers should be aware that the actual functionality behind this endpoint is not documented.

Capabilities

x402-paymentusdc-settlementbase-networkpay-per-requestjson-responseno-api-key

Use cases

  • —Accessing pay-per-request APIs without traditional API key registration
  • —Making micropayments for API calls using USDC on Base
  • —Agent-driven API consumption with x402 payment headers

Fit

Best for

  • —Developers who want keyless, pay-as-you-go API access
  • —AI agents that can settle x402 payments autonomously
  • —Users who prefer crypto micropayments over subscription billing

Not for

  • —Users who need detailed API documentation or schemas before integrating
  • —High-volume callers who would benefit from bulk pricing or subscriptions
  • —Anyone without access to USDC on the Base network

Quick start

curl -X POST https://lowpaymentfee.com/api/v1/payments/257 \
  -H "Content-Type: application/json" \
  -H "X-PAYMENT: <x402-payment-proof>"

Endpoint

URLhttps://lowpaymentfee.com/api/v1/payments/257
Transporthttp
Protocolx402
Pay to0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3
CurrencyUSD COIN

Quality

0.30/ 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 no explanation of what the endpoint actually does beyond the label 'Premium API Access'. The site's docs pages are empty (wallet-connect only). Effectively a stub listing.

Warnings

  • —No documentation available — docs, pricing, and API pages only show 'Connect wallet'
  • —No OpenAPI or request/response schema provided
  • —Unclear what 'Premium API Access' at /api/v1/payments/257 actually returns
  • —The relationship between this endpoint and the other listed APIs is not documented

Citations

Provenance

Indexed fromx402_bazaar
Enriched2026-04-19 06:49:38Z · anthropic/claude-opus-4.6 · v2
First seen2026-04-18
Last seen2026-04-23

Agent access

JSONhttps://clawmart.sh/api/listings/Hjy6B7
Pay-per-call premium API access on Base via x402 — $0.02/request in USDC. — Clawmart · Clawmart