Retrieve portfolio holdings data via x402 micropayment on Base for $0.02 per request.
What it does
This endpoint at lowpaymentfee.com returns holdings data for portfolio #28 via a POST request, gated behind an x402 payment challenge. It is part of a broader platform (lowpaymentfee.com) that offers dozens of pay-per-call APIs spanning data analytics, AI/ML inference, finance/Web3 data, and infrastructure utilities — all priced at $0.02 per request and settled in USDC on the Base network.
The specific endpoint `/api/v1/portfolios/28/holdings` is categorized under the platform's finance and data offerings, though the exact response schema is not documented in the crawled material. The x402 challenge confirms the endpoint is live, accepts USDC (contract 0x8335…2913 on Base), and charges a maximum of 20,000 base units (i.e., $0.02 given USDC's 6 decimals). Payment is made via the x402 `exact` scheme with a 300-second timeout. No API keys or rate limits are advertised; access is granted purely through per-request micropayment.
Documentation is extremely sparse — the docs, pricing, API, and README pages all render only a "Connect wallet" prompt with no further content. There is no OpenAPI spec, no request/response schema, and no usage examples available from the crawl. The endpoint's purpose (portfolio holdings) is inferred solely from the URL path and the generic "Premium API Access" description.
Capabilities
Use cases
- —Fetching holdings data for a specific portfolio via automated agent
- —Integrating portfolio position data into a trading or analytics dashboard
- —Programmatic access to financial holdings without API key management
Fit
Best for
- —Agents that can settle x402 USDC payments on Base
- —Developers wanting keyless, pay-per-call access to portfolio data
- —Micropayment-based workflows needing low-cost financial data
Not for
- —Users who need detailed API documentation or response schemas before integrating
- —High-volume consumers who prefer subscription-based pricing over per-call payments
- —Anyone needing portfolio data for arbitrary portfolio IDs (this endpoint is hardcoded to portfolio 28)
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/portfolios/28/holdings \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is confirmed live via a valid 402 challenge, and pricing is clear ($0.02 USDC on Base). However, there is no OpenAPI spec, no request/response schema, no documentation beyond a wallet-connect prompt, and the endpoint's actual data content is unknown. This is effectively a stub listing.
Warnings
- —No API documentation available — docs, pricing, API, and README pages all show only 'Connect wallet'
- —No request or response schema provided; the data returned by this endpoint is unknown
- —The endpoint is specific to portfolio ID 28; it is unclear whether other portfolio IDs are supported
- —No examples or sample responses available from crawled material
Citations
- —The endpoint returns a 402 challenge with maxAmountRequired of 20000 base units in USDC on Basehttps://lowpaymentfee.com/api/v1/portfolios/28/holdings
- —USDC asset contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/portfolios/28/holdings
- —Platform pricing is $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com