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 88) 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 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 additional technical detail. 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 actual data contract is unknown.
Capabilities
Use cases
- —Retrieving performance metrics for portfolio #88 via a single micropayment
- —Integrating portfolio performance data into an agent workflow without API key management
- —Programmatic access to portfolio analytics settled on Base L2
Fit
Best for
- —Agents or bots that need on-demand portfolio performance data without subscription commitments
- —Developers experimenting with x402 pay-per-call APIs on Base
- —Low-volume consumers who prefer micropayments over monthly plans
Not for
- —Users who need documented request/response schemas before integrating
- —High-volume consumers who would benefit from bulk pricing or subscriptions
- —Anyone needing performance data for portfolios other than ID 88 (no evidence other IDs are supported)
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/portfolios/88/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. Docs pages are empty stubs. The actual data returned is completely unknown, making integration speculative.
Warnings
- —No documentation available — docs, pricing, API, and README pages all show only 'Connect wallet' with no content
- —No OpenAPI or output schema describing request parameters or response fields
- —Portfolio ID 88 is hard-coded in the URL; unclear if other portfolio IDs are valid
- —The provider site lists many API categories but this specific endpoint (/portfolios/88/performance) is not listed on the homepage catalog
Citations
- —Endpoint returns HTTP 402 with x402 challenge on POST, confirming it is livehttps://lowpaymentfee.com/api/v1/portfolios/88/performance
- —Payment asset is USDC on Base network at contract 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 with maxAmountRequired of 20000 base units ($0.02)https://lowpaymentfee.com/api/v1/portfolios/88/performance
- —Provider advertises $0.02/request pricing, no API keys, no rate limits, instant access on Base networkhttps://lowpaymentfee.com
- —Documentation pages (docs, pricing, API, README) render only a 'Connect wallet' prompt with no technical contenthttps://lowpaymentfee.com/docs