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/22/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 infrastructure utilities — 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/22/balance` endpoint actually returns. The landing page lists many other endpoints but provides no detailed documentation for any of them. The endpoint is live (402 challenge confirmed), but the lack of documentation makes it difficult to know what data is returned or what input parameters are expected.
Capabilities
Use cases
- —Querying account balance data via a pay-per-call model without API key registration
- —Integrating x402-compatible agents that can autonomously pay for API access on Base
- —Testing x402 payment flows against a live, low-cost endpoint
Fit
Best for
- —Developers experimenting with x402 payment protocol integrations
- —AI agents that need keyless, pay-per-call API access on Base
- —Projects requiring low-cost ($0.02) per-request data access without subscriptions
Not for
- —Users who need detailed API documentation or response schemas before integrating
- —High-volume use cases where per-request pricing may add up without volume discounts
- —Anyone without a Base-compatible USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/accounts/22/balance \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is live and returns a valid x402 challenge with clear pricing, but there is no documentation, no OpenAPI spec, no request/response examples, and no explanation of what the endpoint actually returns. The /docs and other pages are empty beyond a wallet connect prompt. This is effectively a stub listing.
Warnings
- —No documentation available — /docs, /pricing, /api, and /README pages all show only 'Connect wallet'
- —No OpenAPI or schema describing request parameters or response format for this endpoint
- —The specific resource '/api/v1/accounts/22/balance' is not listed on the landing page among the advertised endpoints, making its purpose unclear
- —No examples of successful responses are available
Citations
- —The endpoint returns a 402 challenge with maxAmountRequired of 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/accounts/22/balance
- —The platform advertises $0.02/request flat pricing with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —USDC asset address 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/accounts/22/balance