x402basequality 0.30

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

Price
0.02 USDC / call
Protocol
x402
Verified
no
Endpoint
https://lowpaymentfee.com/api/v1/portfolios/9

What it does

This endpoint at `/api/v1/portfolios/9` is part of the lowpaymentfee.com platform, which offers a collection of x402-protocol pay-per-call APIs spanning data analytics, AI/ML inference, finance/Web3 data, and infrastructure utilities. The specific `/portfolios/9` resource is listed under "Premium API Access" and returns JSON via POST. Payment is settled on the Base network using USDC (contract `0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913`).

The x402 challenge advertises a `maxAmountRequired` of 20000 base units. USDC uses 6 decimals, so the cost per request is $0.02 (two cents), consistent with the site's uniform $0.02/request pricing across all endpoints. The platform emphasizes simplicity: no API keys, no rate limits, no commitments — just attach an x402 payment header to each call.

Note that the `/portfolios/9` endpoint is not listed on the site's main landing page among the documented API categories (Data & Analytics, AI & ML, Finance & Web3, Infrastructure). Its exact response payload and purpose are unclear — the name "Premium API Access" is generic and no schema or example response is documented. The docs, pricing, and README pages all rendered as empty wallet-connect prompts, so no additional technical documentation was available.

Capabilities

x402-paymentusdc-settlementbase-networkpay-per-requestjson-apiportfolio-data

Use cases

  • —Fetching portfolio data via a single micropayment-gated API call
  • —Integrating pay-per-request data access into autonomous agents
  • —Accessing premium content without API key registration

Fit

Best for

  • —Agents or services that need keyless, pay-per-call API access
  • —Developers experimenting with x402 payment protocol on Base
  • —Use cases requiring low-friction micropayment-gated endpoints

Not for

  • —Users who need detailed API documentation or response schemas before integrating
  • —High-volume consumers who prefer subscription-based pricing over per-call payments

Quick start

curl -X POST https://lowpaymentfee.com/api/v1/portfolios/9 \
  -H "Content-Type: application/json" \
  -H "X-PAYMENT: <x402-payment-token>"

Endpoint

URLhttps://lowpaymentfee.com/api/v1/portfolios/9
Transporthttp
Protocolx402
Pay to0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3
CurrencyUSD COIN

Quality

0.30/ 1.00

The endpoint is live (402 challenge confirmed) and pricing is clear ($0.02/request in USDC on Base). However, the specific /portfolios/9 resource is not documented on the site, no response schema or example is available, and all documentation pages rendered as empty wallet-connect stubs. The purpose and output of this endpoint remain unknown.

Warnings

  • —The /portfolios/9 endpoint is not listed among the site's documented APIs — its purpose and response format are unknown.
  • —All documentation pages (docs, pricing, README) returned only a 'Connect wallet' prompt with no usable content.
  • —No OpenAPI spec, response schema, or example responses are available.
  • —The generic name 'Premium API Access' provides no insight into what data is returned.

Citations

Provenance

Indexed fromx402_bazaar
Enriched2026-04-19 09:06:06Z · anthropic/claude-opus-4.6 · v2
First seen2026-04-18
Last seen2026-04-27

Agent access

JSONhttps://clawmart.sh/api/listings/9Exxu7
x402-gated portfolio endpoint on Base, pay-per-request with USDC. — Clawmart · Clawmart