x402-gated account balance endpoint on Base, pay-per-call with USDC.
What it does
This endpoint at lowpaymentfee.com provides an account balance lookup via the x402 payment protocol. The specific resource `/api/v1/accounts/117/balance` is gated behind a per-request USDC payment on the Base network. The x402 challenge confirms the endpoint is live and accepts exact-scheme payments of up to 20,000 base units of USDC (0.02 USD per request) to the specified payTo address.
The broader lowpaymentfee.com platform advertises a suite of pay-per-call APIs spanning data & analytics (metrics, reports, data export, insights), AI & machine learning (sentiment analysis, text 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 no API keys, no rate limits, and no minimum commitments required. Payments settle in USDC on the Base L2 network.
However, the specific endpoint being listed here — `/api/v1/accounts/117/balance` — does not appear in the site's publicly listed API catalog. Its purpose ("Premium API Access") and response format are not documented. No OpenAPI schema, detailed docs, or example responses were found during the crawl; most documentation pages returned only a "Connect wallet" prompt with no substantive content.
Capabilities
Use cases
- —Querying account balance information via a single paid API call
- —Integrating pay-per-call balance lookups into agent workflows
- —Demonstrating x402 payment protocol integration on Base
Fit
Best for
- —Developers experimenting with x402 payment-gated APIs
- —Agents needing on-demand account balance data without API key management
- —Low-volume, pay-as-you-go API consumption on Base
Not for
- —High-volume balance queries where per-call fees add up
- —Users who need detailed API documentation or guaranteed SLAs
- —Anyone without a Base-compatible USDC wallet
Quick start
# 1. Send a POST to get the 402 challenge
curl -X POST https://lowpaymentfee.com/api/v1/accounts/117/balance
# Response: 402 with x402 payment challenge
# 2. Construct X-PAYMENT header with USDC payment proof on Base
# 3. Resend POST with the X-PAYMENT header to receive the balance responseEndpoint
Quality
The x402 challenge is live and confirms pricing and network, but this specific endpoint is undocumented, has no schema, no example responses, and the docs pages are empty. The endpoint path (/accounts/117/balance) is not listed in the site's public API catalog, making its purpose unclear.
Warnings
- —Endpoint /api/v1/accounts/117/balance is not listed in the site's public API catalog — its function is unclear
- —All documentation pages (docs, api, pricing, README) returned only 'Connect wallet' with no substantive content
- —No OpenAPI spec, request schema, or response schema available
- —The hardcoded account ID '117' in the path suggests this may be a demo or placeholder endpoint
Citations
- —The x402 challenge returns maxAmountRequired of 20000 base units of USDC (asset 0x8335…) on Base networkhttps://lowpaymentfee.com/api/v1/accounts/117/balance
- —All listed APIs are priced at $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —The platform offers APIs across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com