x402-gated account balance endpoint on Base, paid per-call in USDC.
What it does
This endpoint at lowpaymentfee.com provides a "Premium API Access" resource at the path `/api/v1/accounts/85/balance`. It is part of a broader platform that offers dozens of x402-payable API endpoints spanning data analytics, AI/ML inference, finance/Web3 data, and utility services — all settled on the Base network using USDC.
The specific endpoint probed returns an x402 challenge requesting up to 20,000 base units of USDC (0x8335…2913 on Base). Since USDC uses 6 decimals, this translates to $0.02 per request, consistent with the site's advertised flat pricing of $0.02/request across all endpoints. Payment is via the x402 "exact" scheme with a 300-second timeout. No API keys or rate limits are advertised; access is granted purely through the x402 payment header.
Documentation is extremely thin — the /docs, /pricing, /api, and /README pages all render only a "Connect wallet" prompt with no further content. There is no OpenAPI spec, no request/response schema beyond the x402 challenge's `outputSchema` stub, and no explanation of what the `/accounts/85/balance` endpoint actually returns. The endpoint name suggests it retrieves a balance for account ID 85, but the exact response format and semantics are unknown. The platform appears to be a demonstration or early-stage x402 marketplace rather than a mature, documented API provider.
Capabilities
Use cases
- —Querying an account balance behind an x402 paywall
- —Testing x402 payment flows on Base with USDC
- —Demonstrating per-request micropayment API access
Fit
Best for
- —Developers experimenting with x402 protocol payments
- —Agents that can settle USDC on Base for per-call API access
- —Prototyping pay-per-use API integrations without API keys
Not for
- —Production use requiring documented request/response schemas
- —Users who need non-crypto payment methods
- —High-volume use cases where $0.02/call adds up quickly without bulk discounts
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/accounts/85/balance \
-H "X-PAYMENT: <x402-payment-token>" \
-H "Content-Type: application/json"Endpoint
Quality
The endpoint is live and returns a valid x402 challenge with clear pricing ($0.02 USDC on Base). However, there is no OpenAPI spec, no documentation beyond a landing page listing, no request/response examples, and the purpose of this specific endpoint (/accounts/85/balance) is unexplained. Effectively a stub listing.
Warnings
- —No documentation available — /docs, /pricing, /api, and /README pages all show only 'Connect wallet' with no content.
- —No OpenAPI or schema describing request parameters or response format for this endpoint.
- —The purpose and response shape of /api/v1/accounts/85/balance is unknown; 'Premium API Access' is a generic label.
- —Platform may be a demo or early-stage project; maturity is unclear.
Citations
- —The endpoint returns an x402 challenge with maxAmountRequired of 20000 base units of USDC on Base (asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913), equating to $0.02.https://lowpaymentfee.com/api/v1/accounts/85/balance
- —The platform advertises $0.02/request flat pricing with no API keys, no rate limits, and instant access on the Base network.https://lowpaymentfee.com
- —Documentation pages (/docs, /pricing, /api, /README) render only a 'Connect wallet' prompt with no further content.https://lowpaymentfee.com/docs