Portfolio performance data via x402 micropayment on Base network, $0.02/request in USDC.
What it does
This endpoint at lowpaymentfee.com returns portfolio performance data for a specific portfolio (portfolio ID 2) behind an x402 paywall. The endpoint 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 lowpaymentfee.com hosts a broad catalog of x402-gated APIs spanning data analytics, AI/ML inference, finance/Web3 data, and infrastructure utilities — all priced at $0.02 per call. This particular endpoint sits in the finance category and appears to deliver performance metrics for a pre-defined portfolio. No OpenAPI schema, request body documentation, or response examples were found in the crawl; the docs, pricing, and API pages all returned only a "Connect wallet" stub. The exact fields returned by the performance endpoint are unknown.
Because there is no published schema or documentation beyond the landing page listing, agents should treat this as a lightly-documented endpoint. The x402 challenge is live and well-formed, confirming the endpoint is operational and ready to accept payments.
Capabilities
Use cases
- —Retrieve performance metrics for a tracked portfolio
- —Integrate portfolio return data into a dashboard or agent workflow
- —Automated portfolio monitoring with per-call micropayments
Fit
Best for
- —Agents needing on-demand portfolio performance data without API key signup
- —Developers prototyping finance dashboards with pay-per-use pricing
- —x402-compatible wallets exploring low-cost financial data endpoints
Not for
- —Users who need detailed API documentation or response schemas before integrating
- —High-frequency polling where $0.02/request adds up quickly
- —Accessing arbitrary portfolio IDs (this endpoint is hardcoded to portfolio 2)
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/portfolios/2/performance \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402_payment_token>"Endpoint
Quality
The x402 challenge is live and well-formed, confirming the endpoint works and pricing is clear ($0.02 USDC on Base). However, there is no OpenAPI schema, no request/response documentation, and no examples. The docs pages are empty stubs. The purpose of the endpoint is only inferable from the URL path.
Warnings
- —No OpenAPI or request/response schema available — input and output formats are unknown.
- —Documentation pages (/docs, /api, /pricing, /README) all return only a 'Connect wallet' stub with no useful content.
- —Endpoint is specific to portfolio ID 2; it is unclear whether other portfolio IDs are available or what data this portfolio represents.
- —No rate limit or uptime guarantees documented.
Citations
- —The x402 challenge returns maxAmountRequired of 20000 base units in USDC on Base networkhttps://lowpaymentfee.com/api/v1/portfolios/2/performance
- —All APIs on lowpaymentfee.com are priced at $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —USDC asset contract is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/portfolios/2/performance