x402-gated account balance endpoint on Base, pay-per-call with USDC.
What it does
This endpoint at lowpaymentfee.com provides a "Premium API Access" resource at the path /api/v1/accounts/128/balance. It is part of a broader platform offering various pay-per-request APIs spanning data analytics, AI/ML inference, finance/Web3, and infrastructure utilities—all gated via the x402 payment protocol on the Base network.
The specific endpoint accepts POST requests and returns JSON. Payment is settled in USDC (contract 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Base) with a maximum amount required of 20,000 base units, which equals $0.02 USD (USDC uses 6 decimals). The platform advertises a flat $0.02 per request across all endpoints, with no API keys, no rate limits, and no minimum commitments required.
Documentation on the site is extremely sparse—most pages beyond the landing page only show a "Connect wallet" prompt. There is no OpenAPI spec, no detailed request/response schema, and no usage examples available. The endpoint is confirmed live via a valid 402 challenge response. The exact semantics of the "accounts/128/balance" resource are unclear from available materials; it may return account balance information but this is inferred solely from the URL path.
Capabilities
Use cases
- —Querying account balance data with per-request USDC micropayments
- —Integrating pay-as-you-go API access without API key management
- —Agent-driven balance lookups settled on Base L2
Fit
Best for
- —Developers wanting keyless, pay-per-call API access
- —AI agents with Base USDC wallets needing on-demand data
- —Projects requiring low-friction micropayment-gated endpoints
Not for
- —Users needing detailed API documentation or SDKs
- —High-volume use cases where per-request pricing is inefficient
- —Users without a Base-compatible USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/accounts/128/balance \
-H "X-PAYMENT: <x402_payment_token>" \
-H "Content-Type: application/json"Endpoint
Quality
The endpoint is confirmed live with a valid x402 402 challenge, but there is no documentation, no request/response schema, no examples, and the purpose of this specific endpoint (accounts/128/balance) is unclear. The site's docs pages are empty beyond a wallet connect prompt.
Warnings
- —No API documentation available beyond the landing page
- —No request or response schema provided
- —Purpose of /api/v1/accounts/128/balance is unclear—may be a demo or placeholder
- —No OpenAPI spec or ai-plugin manifest found
Citations
- —The endpoint returns a 402 challenge requiring USDC payment of 20000 base units (=$0.02) on Base networkhttps://lowpaymentfee.com/api/v1/accounts/128/balance
- —Platform advertises $0.02/request pricing with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —USDC asset contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/accounts/128/balance