Pay-per-call portfolio holdings API on Base via x402 — $0.02/request in USDC.
What it does
This endpoint at lowpaymentfee.com provides access to portfolio holdings data for portfolio ID 88 via a POST request. It is part of a broader platform (lowpaymentfee.com) that offers numerous pay-per-call APIs spanning data analytics, AI/ML inference, finance/Web3, and infrastructure utilities — all settled on the Base network using USDC through the x402 protocol.
The specific endpoint `/api/v1/portfolios/88/holdings` returns JSON and costs $0.02 per request (20,000 base units of USDC with 6 decimals). Payment is made inline via the X-PAYMENT header; no API keys, accounts, or rate limits are required. The x402 challenge confirms the endpoint is live, accepting the "exact" payment scheme on Base mainnet, paying to address 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3, with a max timeout of 300 seconds.
Documentation is extremely sparse — the docs, pricing, and API pages all render only a "Connect wallet" prompt with no further content. The exact request body schema and response format for this holdings endpoint are not documented anywhere in the crawled material. The endpoint appears to be part of a finance/Web3 category on the platform, but the specific data returned (e.g., token balances, positions, allocation breakdowns) is unknown.
Capabilities
Use cases
- —Retrieving current holdings for a specific portfolio programmatically
- —Integrating portfolio data into dashboards or trading bots
- —Automated portfolio monitoring and alerting
Fit
Best for
- —Agents needing on-demand portfolio holdings without API key management
- —Developers building crypto portfolio trackers on Base
- —Low-volume, pay-as-you-go access to holdings data
Not for
- —High-frequency bulk data retrieval where per-call pricing adds up
- —Users who need detailed documentation or guaranteed SLAs before integrating
- —Accessing portfolios other than ID 88 (only this ID is confirmed)
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/portfolios/88/holdings \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is confirmed live via a valid x402 402 challenge, and pricing is clear ($0.02 USDC on Base). However, there is no documentation of request parameters, response schema, or what 'portfolio 88 holdings' actually contains. Docs pages are empty. This is effectively a stub listing.
Warnings
- —No documentation available — docs, pricing, and API pages all show only 'Connect wallet' with no content
- —Request body schema for POST is completely unknown
- —Response schema and data format are undocumented
- —Only portfolio ID 88 is referenced; unclear if other portfolio IDs are accessible
- —The purpose and data source behind 'portfolio 88' is not explained anywhere
Citations
- —Endpoint returns 402 with x402 challenge confirming it is live on Base network using USDChttps://lowpaymentfee.com/api/v1/portfolios/88/holdings
- —Platform advertises $0.02 per request pricing with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —maxAmountRequired is 20000 base units of USDC (asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) which equals $0.02https://lowpaymentfee.com/api/v1/portfolios/88/holdings