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 23) 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).
lowpaymentfee.com is a broader platform offering multiple x402-gated API categories including data & analytics, AI/ML inference (sentiment, summarization, classification, embeddings), finance & Web3 (price feeds, exchange rates, token quotes, gas estimates), and infrastructure utilities (geocoding, validation, conversion, generation). All endpoints are priced at $0.02 per request with no API keys, no rate limits, and no minimum commitments.
The specific endpoint `/api/v1/portfolios/23/performance` is not listed on the site's main catalog, so its exact response schema and the nature of "portfolio 23" are unclear. The x402 challenge is live and well-formed, confirming the endpoint is operational. Documentation pages (docs, api, pricing, README) all returned only a "Connect wallet" prompt with no substantive content, so detailed request/response schemas are unavailable.
Capabilities
Use cases
- —Retrieving performance metrics for a tracked portfolio
- —Integrating portfolio performance data into dashboards or agents
- —Programmatic access to portfolio returns without API key management
Fit
Best for
- —Agents or apps needing on-demand portfolio performance data with no signup
- —Developers wanting pay-per-call financial data on Base L2
- —Crypto-native workflows that can settle USDC micropayments
Not for
- —Users who need detailed API documentation or response schema guarantees before integrating
- —Bulk historical portfolio analysis requiring thousands of calls at lower cost
- —Non-crypto users without a Base-compatible wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/portfolios/23/performance \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-header>"Endpoint
Quality
The x402 challenge is live and well-formed, confirming the endpoint works and pricing is clear ($0.02 USDC on Base). However, there is no OpenAPI schema, no documentation of request parameters or response format, and the specific portfolio endpoint is not listed in the site's own catalog. All doc pages returned only 'Connect wallet' with no content.
Warnings
- —No request or response schema available — input parameters and output format are unknown
- —The endpoint /api/v1/portfolios/23/performance is not listed on the provider's own landing page catalog
- —All documentation pages (docs, api, pricing, README) returned no substantive content
- —The nature of 'portfolio 23' is unexplained — it may be a demo or a specific user's portfolio
Citations
- —The x402 challenge returns maxAmountRequired of 20000 in USDC (6 decimals) on Base, equaling $0.02https://lowpaymentfee.com/api/v1/portfolios/23/performance
- —The site advertises $0.02/request pricing 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/23/performance