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 #37 via a POST request, gated by the x402 payment protocol. Each call costs $0.02 (20,000 base units of USDC on the Base network, where USDC has 6 decimals). No API keys or rate limits are required — callers simply attach an X-PAYMENT header with a valid x402 payment proof to access the resource.
The provider site (lowpaymentfee.com) hosts a broad catalog of pay-per-call APIs spanning data analytics, AI/ML inference, finance/Web3 data, and utility services, all priced at $0.02 per request and settled in USDC on Base. This specific endpoint falls under the finance category and appears to serve portfolio holdings information, though the exact response schema is not documented. The x402 challenge confirms the endpoint is live, accepts POST, returns application/json, and uses the "exact" payment scheme with a 300-second timeout.
Documentation beyond the landing page is extremely sparse — the /docs, /api, /pricing, and /README pages all render only a "Connect wallet" prompt with no additional technical detail. There is no OpenAPI spec, no example request/response payloads, and no description of what fields the holdings response contains. Callers should expect a JSON response related to portfolio holdings but will need to discover the exact schema empirically.
Capabilities
Use cases
- —Fetching current holdings for a specific portfolio programmatically
- —Integrating portfolio data into trading bots or dashboards
- —Agent-driven portfolio monitoring with per-call micropayments
Fit
Best for
- —Developers wanting keyless, pay-per-call access to portfolio data
- —AI agents that can settle x402 payments on Base
- —Low-volume or sporadic portfolio data lookups without subscription commitments
Not for
- —High-frequency bulk data retrieval where per-call costs add up
- —Users who need detailed API documentation or guaranteed SLAs before integrating
- —Anyone without a Base-compatible USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/portfolios/37/holdings \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402_payment_proof>"Endpoint
Quality
The x402 challenge is live and confirms pricing, network, and payment details, but there is zero documentation on request parameters, response schema, or what 'portfolio 37 holdings' actually contains. No OpenAPI spec, no examples, and all doc pages are empty beyond a wallet connect prompt.
Warnings
- —No API documentation available — /docs, /pricing, /api, and /README all show only 'Connect wallet'
- —No OpenAPI or schema describing request body or response fields for this endpoint
- —The specific portfolio ID (37) is hardcoded in the URL with no explanation of what portfolio it represents
- —Response schema must be discovered empirically; no examples provided by the provider
Citations
- —Endpoint returns HTTP 402 with x402 challenge, confirming it is livehttps://lowpaymentfee.com/api/v1/portfolios/37/holdings
- —Price is $0.02 per request (maxAmountRequired 20000 base units of USDC with 6 decimals on Base)https://lowpaymentfee.com/api/v1/portfolios/37/holdings
- —USDC asset contract on Base: 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/portfolios/37/holdings
- —Provider advertises $0.02/request, no API keys, no rate limits, instant access on Base networkhttps://lowpaymentfee.com
- —Documentation pages (/docs, /api, /pricing, /README) contain only 'Connect wallet' with no technical contenthttps://lowpaymentfee.com/docs