Portfolio performance data via x402 micropayment on Base network, $0.02 per request.
What it does
This endpoint at lowpaymentfee.com provides portfolio performance data for a specific portfolio (ID 81) behind an x402 paywall. The endpoint accepts POST requests and returns JSON. Payment is settled on the Base network using USDC (contract 0x8335…2913) at a cost of $0.02 per request (20,000 base units with 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 uniformly at $0.02 per call. This particular endpoint falls under the finance category and appears to return performance metrics for a portfolio. No API keys or rate limits are advertised; access is granted purely through the x402 payment protocol.
Documentation is extremely sparse. The docs, API, pricing, and README pages all returned only a "Connect wallet" prompt with no substantive content. There is no OpenAPI schema, no request/response examples, and no description of what fields the portfolio performance response contains. The endpoint is confirmed live (402 challenge captured), but the lack of documentation means callers must discover the response shape experimentally.
Capabilities
Use cases
- —Retrieving performance metrics for a tracked portfolio
- —Integrating portfolio performance data into dashboards or agents
- —Paying per-request for financial data without subscriptions or API keys
Fit
Best for
- —Agents needing on-demand portfolio performance data with no signup
- —Developers experimenting with x402 micropayment protocols
- —Use cases requiring low-friction, pay-per-call financial data access
Not for
- —Users who need detailed API documentation or response schema before integrating
- —High-volume consumers who would benefit from bulk pricing or subscriptions
- —Anyone needing portfolio performance for arbitrary portfolio IDs (this endpoint is hardcoded to portfolio 81)
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/portfolios/81/performance \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402_payment_token>"Endpoint
Quality
The endpoint is confirmed live with a valid x402 402 challenge and clear pricing ($0.02 USDC on Base). However, there is no OpenAPI schema, no request/response examples, and all documentation pages are empty stubs. The purpose of the endpoint (portfolio 81 performance) is only inferable from the URL path. This is effectively a stub listing.
Warnings
- —No documentation available — docs, API, pricing, and README pages all return only 'Connect wallet' with no content
- —No OpenAPI or output schema provided; response format is unknown
- —Endpoint is specific to portfolio ID 81; unclear if other portfolio IDs are supported or what portfolio 81 represents
- —No request body schema documented; unclear what parameters (if any) the POST body accepts
Citations
- —Endpoint returns 402 with x402 challenge advertising USDC on Base at maxAmountRequired 20000https://lowpaymentfee.com/api/v1/portfolios/81/performance
- —USDC asset contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/portfolios/81/performance
- —Provider advertises $0.02 per request, no API keys, no rate limits, Base networkhttps://lowpaymentfee.com