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/194/balance` is gated behind a per-request USDC payment on the Base network. The x402 challenge confirms the endpoint is live and accepts POST requests, returning JSON responses.
The parent site lowpaymentfee.com hosts a broader suite of pay-per-call APIs spanning data & analytics, AI/ML (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 advertised at $0.02 per request with no API keys, no rate limits, and no commitments required. Payment settles in USDC on the Base L2 network.
The probed endpoint specifically charges a maximum of 20,000 base units of USDC (0.02 USDC, i.e., $0.02) per call, consistent with the site's uniform pricing. However, documentation beyond the landing page is essentially empty (all sub-pages just show "Connect wallet"), so the exact request format, required parameters, and response schema for this particular balance endpoint are unknown. There is no OpenAPI spec or detailed API documentation available.
Capabilities
Use cases
- —Querying account balance information via a single paid API call
- —Integrating pay-per-use balance lookups into agent workflows without managing API keys
- —Programmatic account balance checks settled in USDC on Base
Fit
Best for
- —Agents needing keyless, pay-per-call account balance data
- —Developers testing x402 payment protocol integrations
- —Scenarios requiring low-friction API access without subscriptions
Not for
- —High-volume balance polling where $0.02/request adds up quickly
- —Use cases requiring detailed API documentation or guaranteed SLAs
- —Users who need fiat-only payment rails
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/accounts/194/balance \
-H "X-PAYMENT: <x402_payment_token>" \
-H "Content-Type: application/json"Endpoint
Quality
The endpoint is live (402 challenge confirmed) and pricing is clear ($0.02 USDC on Base), but there is no API documentation, no OpenAPI spec, no request/response schema, and all doc pages are empty. The purpose of this specific balance endpoint (account 194) is opaque. This is effectively a stub listing.
Warnings
- —No API documentation available — all doc/pricing/README pages return only 'Connect wallet'
- —No OpenAPI or schema describing request parameters or response format
- —The endpoint path references a specific account ID (194); unclear if this is parameterizable or a fixed demo
- —The broader site advertises many API categories but none have documented schemas
Citations
- —Endpoint returns 402 with x402 challenge requiring USDC payment on Base networkhttps://lowpaymentfee.com/api/v1/accounts/194/balance
- —Max amount required is 20000 base units of USDC (0.02 USD) per requesthttps://lowpaymentfee.com/api/v1/accounts/194/balance
- —Site advertises $0.02/request pricing with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —USDC asset contract on Base: 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/accounts/194/balance