x402-gated portfolio endpoint on Base, pay $0.02 per request in USDC — no API keys needed.
What it does
This endpoint at lowpaymentfee.com provides premium API access to a specific portfolio resource (portfolio ID 92) via the x402 payment protocol. It is part of a broader platform that offers dozens of pay-per-call endpoints spanning data analytics, AI/ML inference, finance/Web3 data, and infrastructure utilities — all gated behind x402 micro-payments on the Base network.
The endpoint accepts POST requests and returns JSON. Payment is settled in USDC (contract 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Base) using the "exact" scheme. The maximum amount required per call is 20,000 base units of USDC, which equals $0.02 (USDC uses 6 decimals). No API keys, rate limits, or upfront commitments are required — callers simply attach an X-PAYMENT header with a valid x402 payment proof.
The specific data returned by the /api/v1/portfolios/92 endpoint is not documented in the crawled material. The platform's landing page groups its APIs into categories like "Data & Analytics," "AI & Machine Learning," "Finance & Web3," and "Infrastructure," but the portfolios path does not appear in any of those listed categories. Without further documentation or example responses, the exact schema and content of the portfolio resource remain unknown.
Capabilities
Use cases
- —Retrieving portfolio data without needing an API key or subscription
- —Agent-driven workflows that need on-demand paid data access
- —Integrating micro-payment-gated data into automated trading or analytics pipelines
Fit
Best for
- —Developers who want keyless, pay-as-you-go API access
- —AI agents with x402 payment capability on Base
- —Users who prefer crypto micro-payments over traditional subscriptions
Not for
- —Users who need free or ad-supported data access
- —Applications requiring high-throughput bulk data (no documented batch endpoint)
- —Users without a Base-compatible USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/portfolios/92 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-proof>"Endpoint
Quality
The endpoint is live (402 challenge captured) and pricing is clear ($0.02 USDC on Base), but there is no documentation for the /portfolios/92 resource — no input schema, no output schema, no example responses. The crawled docs/pricing/README pages all returned only a 'Connect wallet' stub with no useful content.
Warnings
- —No documentation exists for the /api/v1/portfolios/92 endpoint — its purpose and response schema are unknown.
- —The docs, pricing, API, and README pages all render only a 'Connect wallet' prompt with no substantive content.
- —The portfolios path is not listed among the platform's advertised API categories, raising questions about whether this is a production resource.
Citations
- —The endpoint returns a 402 challenge requiring USDC payment on Base with maxAmountRequired of 20000 base units ($0.02).https://lowpaymentfee.com/api/v1/portfolios/92
- —The platform advertises $0.02/request pricing with no API keys, no rate limits, and instant access on the Base network.https://lowpaymentfee.com
- —USDC asset contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913.https://lowpaymentfee.com/api/v1/portfolios/92