Portfolio holdings data via x402 micropayment on Base network, $0.02 per request.
What it does
This endpoint at lowpaymentfee.com returns portfolio holdings data for a specific portfolio (ID 45) behind an x402 paywall. It is part of a broader platform offering data & analytics, AI/ML inference, finance/Web3, and infrastructure APIs — all priced at $0.02 per request and settled in USDC on the Base network.
The endpoint accepts POST requests and returns JSON. Payment is handled via the x402 protocol: callers receive a 402 challenge containing the payment details (asset, amount, recipient address), construct an on-chain USDC payment on Base, and include the payment proof in the X-PAYMENT header on a subsequent request. The max amount required is 20,000 base units of USDC (6 decimals), which equals $0.02. No API keys, rate limits, or upfront commitments are needed.
The specific data returned by this holdings endpoint is not documented in detail — the platform's docs, pricing, and README pages all render only a wallet-connect prompt with no additional content. The endpoint path suggests it returns the current holdings of portfolio #45, likely including asset names, quantities, and possibly valuations, but this is inferred from the URL structure alone. The platform advertises itself under a "Finance & Web3" category with price feeds, exchange rates, token quotes, and gas estimates as sibling endpoints.
Capabilities
Use cases
- —Retrieving current holdings for a tracked portfolio
- —Building portfolio dashboards that pull live holding data
- —Automated agents querying portfolio composition without API key management
- —On-demand portfolio snapshots paid per request via USDC
Fit
Best for
- —Agents or apps that need pay-per-call portfolio data without subscriptions
- —Developers experimenting with x402 micropayment protocols
- —Lightweight integrations that want no-auth, no-rate-limit access to financial data
Not for
- —Users who need detailed API documentation or schema guarantees before integrating
- —High-frequency bulk data retrieval where per-request pricing adds up
- —Anyone without a Base-network USDC wallet or x402-compatible client
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/portfolios/45/holdings \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-proof>"Endpoint
Quality
The endpoint is live (402 challenge confirmed) and pricing is clear ($0.02 USDC on Base). However, there is no OpenAPI schema, no response examples, no request body documentation, and the docs/pricing/README pages are all empty wallet-connect stubs. The actual data returned is entirely unknown.
Warnings
- —No documentation available — docs, pricing, and README pages only show a wallet-connect prompt with no content.
- —No request or response schema is published; the shape of the holdings data is unknown.
- —Portfolio ID 45 is hardcoded in the path; it is unclear whether other portfolio IDs are available or what they represent.
- —The platform lists many endpoint categories but this specific endpoint (/portfolios/45/holdings) is not listed on the homepage.
Citations
- —The endpoint returns a 402 challenge with maxAmountRequired of 20000 base units of USDC on Base network.https://lowpaymentfee.com/api/v1/portfolios/45/holdings
- —The platform prices all APIs at $0.02 per request with no API keys, no rate limits, and instant access on the Base network.https://lowpaymentfee.com
- —The USDC asset address is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Base.https://lowpaymentfee.com/api/v1/portfolios/45/holdings