x402basequality 0.35

Pay-per-call portfolio holdings API on Base via x402, settled in USDC at $0.02/request.

Price
0.02 USDC / call
Protocol
x402
Verified
no
Endpoint
https://lowpaymentfee.com/api/v1/portfolios/23/holdings

What it does

This endpoint at lowpaymentfee.com provides access to portfolio holdings data (portfolio ID 23) via the x402 payment protocol. It accepts POST requests and returns JSON. Payment is settled on the Base network using USDC (contract 0x8335…2913) with a maximum cost of 20,000 base units, which equals $0.02 per request (USDC uses 6 decimals).

The provider site lowpaymentfee.com hosts a broad catalog of pay-per-call APIs spanning data analytics, AI/ML inference, finance/Web3 data, and infrastructure utilities — all priced at $0.02 per request with no API keys, no rate limits, and no commitments. This specific endpoint falls under the finance/portfolio category. The x402 challenge was successfully captured (HTTP 402 with valid accepts payload), confirming the endpoint is live.

Documentation is extremely sparse — the docs, API, pricing, and README pages all returned only a "Connect wallet" prompt with no further content. There is no OpenAPI schema, no request/response examples, and no description of what fields the holdings response contains or what POST body (if any) is expected. The endpoint is functional from a payment-protocol standpoint, but consumers should expect to experiment with request payloads to discover the actual data contract.

Capabilities

x402-paymentusdc-settlementbase-networkportfolio-holdingspay-per-callno-api-keyjson-response

Use cases

  • —Retrieving portfolio holdings data for a specific portfolio without needing an API key
  • —Integrating portfolio data into agent workflows that can settle payments via x402
  • —Building dashboards or analytics on top of portfolio composition data

Fit

Best for

  • —Agents or apps that can pay per-call via x402 on Base
  • —Users who want keyless, instant access to portfolio data
  • —Micropayment-friendly integrations needing low per-request costs

Not for

  • —Users who need detailed API documentation or guaranteed response schemas before integrating
  • —High-volume batch consumers who need bulk pricing or subscription plans
  • —Anyone unable to settle USDC payments on the Base network

Quick start

curl -X POST https://lowpaymentfee.com/api/v1/portfolios/23/holdings \
  -H "Content-Type: application/json" \
  -H "X-PAYMENT: <x402-payment-header>"

Endpoint

URLhttps://lowpaymentfee.com/api/v1/portfolios/23/holdings
Transporthttp
Protocolx402
Pay to0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3
CurrencyUSD COIN

Quality

0.35/ 1.00

The x402 challenge is live and pricing is clear ($0.02/request in USDC on Base). However, there is no OpenAPI schema, no request/response examples, and all documentation pages are empty stubs. The actual data contract for this holdings endpoint is completely unknown.

Warnings

  • —No API documentation available — docs, pricing, and README pages all return only a wallet-connect prompt with no content.
  • —No OpenAPI or JSON schema describing request body or response format for this endpoint.
  • —The specific portfolio ID (23) is hardcoded in the URL; it is unclear whether other portfolio IDs are available or what they represent.
  • —Response structure is entirely unknown — consumers must discover the data contract experimentally.

Citations

Provenance

Indexed fromx402_bazaar
Enriched2026-04-19 08:20:08Z · anthropic/claude-opus-4.6 · v2
First seen2026-04-18
Last seen2026-04-28

Agent access

JSONhttps://clawmart.sh/api/listings/x6nb7T
Pay-per-call portfolio holdings API on Base via x402, settled in USDC at $0.02/request. — Clawmart · Clawmart