Pay-per-call portfolio data endpoint on Base via x402, settled in USDC at $0.02/request.
What it does
This x402-enabled endpoint at lowpaymentfee.com serves portfolio data at `/api/v1/portfolios/1` via HTTP POST. It uses the x402 payment protocol on the Base network, accepting USDC (contract 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) with a maximum cost of $0.02 per request (20,000 base units at 6 decimals). No API keys or rate limits are required — payment is handled inline via the X-PAYMENT header.
The provider, lowpaymentfee.com, offers a broader catalog of pay-per-call APIs spanning data analytics, AI/ML inference (sentiment analysis, summarization, classification, embeddings), finance/Web3 (price feeds, exchange rates, token quotes, gas estimates), and infrastructure utilities (geocoding, validation, conversion, generation). All endpoints are listed at $0.02 per request with the same x402 payment model on Base.
The specific endpoint being listed here (`/api/v1/portfolios/1`) is described only as "Premium API Access" with no further documentation on request parameters or response schema. The docs, pricing, and API pages on the site require a wallet connection and provide no additional technical detail. Because of this, the exact data returned by this portfolio endpoint is unclear — it likely returns portfolio-related JSON data, but the structure and fields are undocumented.
Capabilities
Use cases
- —Retrieving portfolio data on-demand with per-call USDC micropayments
- —Agent-driven portfolio lookups without managing API keys
- —Integrating low-cost financial data into automated workflows
Fit
Best for
- —Agents or bots that need keyless, pay-as-you-go portfolio data access
- —Developers experimenting with x402 payment protocol on Base
- —Low-volume consumers who want no subscription commitments
Not for
- —High-volume bulk data consumers who need flat-rate pricing
- —Users who need detailed API documentation or guaranteed SLAs
- —Anyone without access to USDC on the Base network
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/portfolios/1 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is live (402 challenge captured) and pricing is clear ($0.02 USDC on Base), but there is no documentation on request parameters, response schema, or what 'portfolios/1' actually returns. Docs pages require wallet connection and yield no content. Effectively a stub listing.
Warnings
- —No documentation available — docs/pricing/API pages all require wallet connection and show no content
- —Request body schema and response schema are completely undocumented
- —The meaning of 'portfolios/1' (whether '1' is a fixed resource or a portfolio ID) is unclear
- —No OpenAPI spec or examples provided by the provider
Citations
- —Endpoint returns 402 with x402 challenge accepting USDC on Base network at maxAmountRequired 20000https://lowpaymentfee.com/api/v1/portfolios/1
- —USDC asset contract is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/portfolios/1
- —All endpoints priced at $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —Provider offers additional API categories including Data & Analytics, AI & ML, Finance & Web3, and Infrastructurehttps://lowpaymentfee.com