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/charges/394

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/charges/394` is listed as "Premium API Access" and returns a valid x402 challenge with a maxAmountRequired of 20,000 base units of USDC (0x8335…2913 on Base), which equals $0.02. Payment is made via the x402 exact scheme — no API keys, no rate limits, and no subscriptions required. The endpoint accepts POST requests and returns application/json.

Documentation is extremely sparse: the /docs, /pricing, /api, and /README pages all render only a "Connect wallet" prompt with no further content. There is no OpenAPI spec, no request/response schema documentation, and no examples of what this particular endpoint actually returns. The site's landing page confirms the pricing model and lists available endpoints, but does not describe the input parameters or output format for any of them. Without knowing what data or functionality `/api/v1/charges/394` specifically provides, agents should treat this as an opaque premium endpoint until more documentation surfaces.

Capabilities

x402-paymentusdc-settlementbase-networkpay-per-requestno-api-keyjson-response

Use cases

  • —Accessing premium API functionality with per-request USDC micropayments on Base
  • —Agent-driven API consumption without API key management
  • —Pay-as-you-go data or service access settled on-chain

Fit

Best for

  • —Agents or applications that need keyless, on-demand API access
  • —Users who prefer crypto micropayments over subscription billing
  • —Developers experimenting with x402 protocol integrations

Not for

  • —Users who need detailed API documentation or guaranteed SLAs before purchasing
  • —High-volume consumers who would benefit from bulk pricing or subscriptions
  • —Anyone unable to transact in USDC on the Base network

Quick start

# 1. Send a POST to get the x402 payment challenge
curl -X POST https://lowpaymentfee.com/api/v1/charges/394
# Returns 402 with x402 payment challenge
# 2. Construct X-PAYMENT header per x402 spec, pay 0.02 USDC on Base
curl -X POST https://lowpaymentfee.com/api/v1/charges/394 \
  -H "X-PAYMENT: <signed-payment-token>"

Endpoint

URLhttps://lowpaymentfee.com/api/v1/charges/394
Transporthttp
Protocolx402
Pay to0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3
CurrencyUSD COIN

Quality

0.30/ 1.00

The endpoint is live and returns a valid x402 challenge, confirming pricing and payment details. However, there is no OpenAPI spec, no documentation of request parameters or response schema, and the specific functionality of /api/v1/charges/394 is entirely undocumented. The docs/pricing/README pages are all blank beyond a wallet connect prompt.

Warnings

  • —No documentation available — /docs, /pricing, /api, and /README pages all show only 'Connect wallet' with no content.
  • —No OpenAPI or schema definition found for any endpoint.
  • —The specific functionality of /api/v1/charges/394 ('Premium API Access') is not described anywhere — unclear what it returns.
  • —No request or response examples are available.

Citations

Provenance

Indexed fromx402_bazaar
Enriched2026-04-19 04:02:39Z · anthropic/claude-opus-4.6 · v2
First seen2026-04-18
Last seen2026-04-22

Agent access

JSONhttps://clawmart.sh/api/listings/8yZKBS
Pay-per-call premium API access on Base via x402 — $0.02/request in USDC. — Clawmart · Clawmart