Pay-per-call portfolio holdings API on Base via x402, settled in USDC at $0.02/request.
What it does
This endpoint at lowpaymentfee.com provides access to portfolio holdings data (portfolio ID 12) via a POST request. It is part of a broader platform offering data & analytics, AI/ML, finance/Web3, and infrastructure APIs, all priced at $0.02 per request with no API keys, no rate limits, and no commitments.
Payment is handled through the x402 protocol on the Base network. The endpoint accepts USDC (contract 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) with a max amount of 20,000 base units, which equals $0.02 (USDC uses 6 decimals). The payment scheme is "exact," meaning each call requires a single micropayment. The timeout for payment settlement is 300 seconds.
The specific endpoint `/api/v1/portfolios/12/holdings` appears to be a finance-related resource returning portfolio holdings in JSON format. However, documentation is extremely sparse — the docs, API, pricing, and README pages all render only a "Connect wallet" prompt with no further detail. There is no OpenAPI schema, no request/response examples, and no description of what fields the holdings response contains or what parameters the POST body accepts. The endpoint is confirmed live (402 challenge captured), but the lack of documentation makes integration speculative.
Capabilities
Use cases
- —Retrieving portfolio holdings data for a specific portfolio
- —Integrating on-chain micropayment-gated financial data into agent workflows
- —Accessing holdings information without traditional API key registration
Fit
Best for
- —Agents or apps that need portfolio holdings data with zero onboarding friction
- —Developers experimenting with x402 pay-per-call patterns on Base
- —Low-volume consumers who prefer per-request pricing over subscriptions
Not for
- —Users needing detailed API documentation or request/response schemas before integrating
- —High-volume consumers who would benefit from bulk pricing or subscriptions
- —Anyone requiring non-USDC or non-Base payment settlement
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/portfolios/12/holdings \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-header>"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 schema, no request/response examples, and all documentation pages return only a 'Connect wallet' stub. The specific purpose of portfolio 12 holdings is unexplained. This is effectively a stub listing.
Warnings
- —No API documentation available — docs, API, pricing, and README pages all show only 'Connect wallet'
- —No OpenAPI or request/response schema provided; request body format is unknown
- —The endpoint is specific to portfolio ID 12 with no explanation of what this portfolio represents
- —No information on what fields the holdings response contains
Citations
- —Endpoint returns 402 with x402 challenge advertising USDC on Base, maxAmountRequired 20000 base unitshttps://lowpaymentfee.com/api/v1/portfolios/12/holdings
- —Platform pricing is $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —USDC asset contract is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/portfolios/12/holdings
- —Docs, API, pricing, and README pages render only 'Connect wallet'https://lowpaymentfee.com/docs