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 73) behind an x402 paywall. It 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 call. This specific endpoint falls under the finance category and appears to return performance metrics for a given portfolio. No API keys or rate limits are advertised; access is granted purely via the x402 payment header.
Documentation is extremely sparse. The docs, pricing, API, and README pages all render only a "Connect wallet" prompt with no further technical detail. There is no OpenAPI spec, no request/response schema, and no example payloads available. The endpoint is confirmed live (returns a proper 402 challenge), but the actual shape of the response and any required request body fields are unknown.
Capabilities
Use cases
- —Retrieve performance metrics for a tracked portfolio
- —Integrate portfolio performance data into dashboards or trading bots
- —Agent-driven portfolio monitoring with per-call micropayments
Fit
Best for
- —Developers needing on-demand portfolio performance data without subscriptions
- —AI agents that can settle x402 payments on Base
- —Projects wanting keyless, pay-per-use financial data
Not for
- —Users who need detailed API documentation or schemas before integrating
- —Bulk historical data downloads (pay-per-request model may be costly at scale)
- —Non-crypto users who cannot settle USDC payments on Base
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/portfolios/73/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, but there is no OpenAPI spec, no request/response schema, no documentation beyond a wallet-connect prompt, and no examples. The portfolio endpoint itself is not listed on the provider's homepage catalog. Effectively a stub with confirmed liveness.
Warnings
- —No OpenAPI or schema available — request body and response shape are entirely unknown
- —Documentation pages (docs, pricing, API, README) all render only 'Connect wallet' with no content
- —This specific portfolio endpoint (/portfolios/73/performance) is not listed in the provider's public API catalog
- —No information on what portfolio ID 73 represents or whether other portfolio IDs are accessible
Citations
- —Endpoint returns HTTP 402 with x402 challenge on POST, confirming it is livehttps://lowpaymentfee.com/api/v1/portfolios/73/performance
- —Payment is 20,000 base units of USDC (USD Coin) on Base network, equaling $0.02https://lowpaymentfee.com/api/v1/portfolios/73/performance
- —Provider advertises $0.02/request, 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/73/performance