Portfolio performance data via x402 micropayment on Base network, $0.02/request in USDC.
What it does
This endpoint at lowpaymentfee.com provides portfolio performance data for a specific portfolio (ID 49) 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 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 minimum commitments. This specific endpoint sits under the finance category and appears to return performance metrics for a pre-defined portfolio. However, no detailed documentation, request schema, or response schema is available beyond the x402 challenge metadata. The docs, pricing, and API pages on the site all render only a "Connect wallet" prompt with no further content.
Because there is no OpenAPI spec, no example responses, and no documentation describing what fields the portfolio performance response contains or what POST body parameters (if any) are accepted, consumers should treat this as a lightly-documented endpoint. The x402 challenge is live and well-formed, confirming the endpoint is operational.
Capabilities
Use cases
- —Retrieving performance metrics for a tracked portfolio
- —Integrating portfolio performance data into dashboards or agents
- —Programmatic access to portfolio returns without API key management
Fit
Best for
- —Agents or apps needing on-demand portfolio performance data with micropayments
- —Developers who want keyless, pay-per-call financial data access on Base
- —Prototyping financial dashboards without subscription commitments
Not for
- —Users needing detailed API documentation or guaranteed SLAs before integrating
- —Bulk historical portfolio backtesting requiring thousands of cheap calls (no volume discounts documented)
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/portfolios/49/performance \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The x402 challenge is live and pricing is clear ($0.02 USDC on Base), but there is no OpenAPI spec, no request/response schema, no documentation beyond a landing page listing, and no example payloads. The endpoint is effectively a stub listing with confirmed liveness.
Warnings
- —No API documentation available — docs, pricing, and API pages only show 'Connect wallet' with no content.
- —No request body schema or response schema documented; consumers cannot know what parameters to send or what fields to expect.
- —Portfolio ID 49 is hardcoded in the URL; unclear if other portfolio IDs are available or how they are discovered.
- —The provider site lists many endpoints across categories but none appear to have public documentation.
Citations
- —The x402 challenge returns maxAmountRequired of 20000 base units in USDC on Base networkhttps://lowpaymentfee.com/api/v1/portfolios/49/performance
- —USDC asset contract is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/portfolios/49/performance
- —All APIs on the site are priced at $0.02 per request with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com