x402basequality 0.30

x402-gated portfolio transactions endpoint on Base, pay-per-call with USDC.

Price
0.02 USDC / call
Protocol
x402
Verified
no
Endpoint
https://lowpaymentfee.com/api/v1/portfolios/90/transactions

What it does

This endpoint at lowpaymentfee.com provides access to portfolio transaction data via an x402 payment-gated POST request. The specific resource `/api/v1/portfolios/90/transactions` is part of a broader platform (lowpaymentfee.com) that offers dozens of pay-per-request APIs spanning data analytics, AI/ML inference, finance/Web3 data, and utility services — all settled on the Base network using USDC.

The x402 challenge confirms the endpoint is live and accepts payments via the "exact" scheme on Base mainnet. The maximum amount required per call is 20,000 base units of USDC (0x8335…2913), which equals $0.02 USD (USDC uses 6 decimals). The platform advertises a flat $0.02/request pricing model with no API keys, no rate limits, and instant access.

Documentation is extremely sparse — the docs, API, pricing, and README pages all render only a "Connect wallet" prompt with no substantive content. There is no OpenAPI schema, no request/response examples, and no description of what the portfolio transactions endpoint actually returns or what parameters it accepts. The endpoint path suggests it retrieves or creates transactions for portfolio ID 90, but this is inference only. The platform appears to be a demonstration or early-stage x402 API marketplace.

Capabilities

x402-paymentusdc-settlementbase-networkportfolio-transactionspay-per-requestno-api-key

Use cases

  • —Retrieving or submitting portfolio transaction records via a single paid API call
  • —Integrating pay-per-request financial data into agent workflows without API key management
  • —Demonstrating x402 payment protocol integration on Base

Fit

Best for

  • —Developers experimenting with x402 payment-gated APIs
  • —Agents needing keyless, pay-per-call access to portfolio data
  • —Projects exploring micropayment-settled API consumption on Base

Not for

  • —Production use cases requiring documented request/response schemas
  • —High-volume batch data retrieval where per-call pricing is inefficient
  • —Users who need detailed API documentation before integration

Quick start

curl -X POST https://lowpaymentfee.com/api/v1/portfolios/90/transactions \
  -H "Content-Type: application/json" \
  -H "X-PAYMENT: <x402-payment-header>"

Endpoint

URLhttps://lowpaymentfee.com/api/v1/portfolios/90/transactions
Transporthttp
Protocolx402
Pay to0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3
CurrencyUSD COIN

Quality

0.30/ 1.00

The endpoint is live and returns a valid x402 challenge with clear pricing ($0.02 USDC on Base). However, there is no OpenAPI schema, no request/response documentation, no examples, and the docs pages are empty. The purpose of this specific endpoint (portfolio 90 transactions) is unclear beyond path inference.

Warnings

  • —No API documentation available — docs, pricing, and README pages all show only 'Connect wallet'
  • —No OpenAPI or JSON schema describing request parameters or response format
  • —The specific portfolio ID '90' in the path is unexplained — unclear if this is a fixed demo or parameterizable
  • —Platform appears to be early-stage or a demonstration; reliability and data quality are unknown

Citations

Provenance

Indexed fromx402_bazaar
Enriched2026-04-19 09:05:13Z · anthropic/claude-opus-4.6 · v2
First seen2026-04-18
Last seen2026-04-27

Agent access

JSONhttps://clawmart.sh/api/listings/x6sYXE
x402-gated portfolio transactions endpoint on Base, pay-per-call with USDC. — Clawmart · Clawmart