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 84) 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, and infrastructure utilities — all priced at $0.02 per call. This particular endpoint falls under the finance category and appears to return performance metrics for a pre-defined portfolio. No API keys or rate limits are advertised; access is granted purely through the x402 payment protocol.
Documentation is extremely sparse. The docs, pricing, API, and README pages all render 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 or what parameters the POST body accepts. The endpoint is confirmed live (returns a proper 402 challenge), but the lack of documentation means callers must experiment to discover the actual input/output contract.
Capabilities
Use cases
- —Retrieving performance metrics for portfolio #84 via a single micropayment
- —Programmatic portfolio monitoring without API key management
- —Agent-driven financial data retrieval using x402 protocol
Fit
Best for
- —Developers experimenting with x402 payment protocol
- —Agents needing low-friction, keyless access to portfolio data
- —Micropayment-based financial data consumption
Not for
- —Users needing documented, well-specified API contracts
- —Querying arbitrary or custom portfolio IDs (endpoint is fixed to portfolio 84)
- —High-volume analytics requiring bulk or subscription pricing
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/portfolios/84/performance \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is live and returns a valid x402 challenge with clear pricing, but there is zero documentation on request parameters or response schema. The docs pages are empty stubs. The specific purpose of 'portfolio 84 performance' is unexplained, making this effectively a stub listing.
Warnings
- —No documentation available — docs, pricing, API, and README pages all show only 'Connect wallet' with no content
- —No OpenAPI or request/response schema provided; input and output formats are unknown
- —Endpoint is hardcoded to portfolio ID 84 with no explanation of what this portfolio represents
- —Cannot verify what data is actually returned without making a paid request
Citations
- —Endpoint returns 402 with x402 challenge advertising USDC on Base at maxAmountRequired 20000https://lowpaymentfee.com/api/v1/portfolios/84/performance
- —All APIs priced at $0.02/request with no API keys, no rate limits, instant access on Base networkhttps://lowpaymentfee.com
- —USDC asset contract is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/portfolios/84/performance