Retrieve portfolio holdings via x402 micropayment on Base for $0.02 per request.
What it does
This endpoint at lowpaymentfee.com returns holdings data for portfolio ID 3. It is part of a broader platform (lowpaymentfee.com) that offers dozens of pay-per-call API endpoints spanning data analytics, AI/ML inference, finance/Web3, and infrastructure utilities — all priced at $0.02 per request and settled via x402 using USDC on the Base network.
The specific endpoint `/api/v1/portfolios/3/holdings` accepts POST requests and returns JSON. The x402 challenge confirms it is live, requiring a maximum payment of 20,000 base units of USDC (0x8335…2913 on Base). Since USDC uses 6 decimals, this equals $0.02 per call. Payment is made via the x402 "exact" scheme to wallet 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3 with a 300-second timeout.
Documentation is extremely sparse. The crawled /docs, /api, /pricing, and /README pages all returned only a "Connect wallet" prompt with no additional content. There is no OpenAPI spec, no request/response schema, and no example payloads available. The endpoint's purpose — portfolio holdings — is inferred solely from the URL path and the site's "Finance & Web3" category listing. The actual request body format and response structure are unknown.
Capabilities
Use cases
- —Fetching current holdings for a specific portfolio
- —Integrating portfolio data into dashboards or trading bots
- —Agent-driven portfolio monitoring with per-call micropayments
Fit
Best for
- —Developers needing keyless, pay-per-call portfolio data access
- —AI agents that can settle x402 payments on Base
- —Users who want no-commitment API access without subscriptions
Not for
- —Users who need detailed API documentation or schemas before integrating
- —High-volume consumers who would prefer bulk/subscription pricing
- —Anyone without a Base-compatible USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/portfolios/3/holdings \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-header>"Endpoint
Quality
The endpoint is live (402 challenge confirmed) and pricing is clear ($0.02 USDC on Base), but there is no documentation, no OpenAPI spec, no request/response schema, and no examples. The actual data returned is unknown — the endpoint's purpose is inferred only from its URL path. This is effectively a stub listing.
Warnings
- —No API documentation available — /docs, /api, /pricing, and /README all return only a wallet-connect prompt
- —No OpenAPI or JSON schema for request or response bodies
- —The endpoint path includes a hardcoded portfolio ID (3); it is unclear if other portfolio IDs are supported or what data is returned
- —The platform appears to be a generic demo or showcase site with many listed endpoints but no substantive documentation for any of them
Citations
- —The endpoint returns a 402 challenge with maxAmountRequired of 20000 base units of USDC on Base (asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913), equaling $0.02https://lowpaymentfee.com/api/v1/portfolios/3/holdings
- —The site advertises $0.02 per request pricing with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —The platform lists endpoints across Data & Analytics, AI & Machine Learning, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com
- —Documentation pages (/docs, /api, /pricing, /README) contain only a 'Connect wallet' prompt with no substantive contenthttps://lowpaymentfee.com/docs