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 16) 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 site 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 request. 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 description of request parameters, and no example responses. The endpoint is confirmed live (returns a valid 402 challenge), but the actual shape of the response and what "portfolio performance" includes (returns, time series, benchmarks, etc.) is unknown.
Capabilities
Use cases
- —Retrieving performance metrics for a tracked portfolio
- —Agent-driven portfolio monitoring with per-request micropayments
- —Integrating portfolio performance data into dashboards without API key management
Fit
Best for
- —Agents or apps needing on-demand portfolio performance data with no subscription
- —Developers exploring x402 micropayment-gated finance APIs
- —Low-volume, pay-per-use portfolio analytics
Not for
- —Users needing detailed API documentation or schema guarantees before integration
- —High-frequency trading or latency-sensitive applications (no SLA documented)
- —Users who cannot transact in USDC on Base network
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/portfolios/16/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 no documentation, no OpenAPI schema, no request/response examples, and no description of what portfolio 16 is or what the performance response contains. Effectively a stub listing.
Warnings
- —No API documentation available — docs, pricing, API, and README pages all show only 'Connect wallet'
- —No OpenAPI or output schema provided; response format is entirely unknown
- —The specific portfolio (ID 16) is not described — unclear what asset class or strategy it represents
- —No SLA, rate limit, or uptime guarantees documented
Citations
- —Endpoint returns a valid x402 402 challenge with maxAmountRequired of 20000 base units in USDC on Basehttps://lowpaymentfee.com/api/v1/portfolios/16/performance
- —All APIs on the site 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 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/portfolios/16/performance