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" account balance resource at `/api/v1/accounts/57/balance`. It is part of a broader platform that offers a variety of pay-per-request APIs spanning data analytics, AI/ML inference, finance/Web3 data, and utility services — all gated via the x402 payment protocol on the Base network.
The specific endpoint probed returns an x402 challenge requesting payment in USDC (contract `0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913` on Base) with a `maxAmountRequired` of 20,000 base units. Since USDC uses 6 decimals, this translates to $0.02 per request, consistent with the platform's advertised flat pricing of $0.02/request across all endpoints. Payment is made via the `exact` scheme, and the endpoint accepts POST requests.
The platform advertises no API keys, no rate limits, and instant access. Documentation pages (`/docs`, `/pricing`, `/api`, `/README`) all returned only a "Connect wallet" prompt with no substantive content, so the actual response schema and detailed behavior of this specific balance endpoint are unknown. The endpoint is live and returning a well-formed x402 challenge, but the lack of documentation means the exact data returned after payment is not documented.
Capabilities
Use cases
- —Querying account balance data behind a micropayment wall
- —Demonstrating x402 payment protocol integration on Base
- —Agent-driven pay-per-request data retrieval without API keys
Fit
Best for
- —Developers experimenting with x402 payment-gated APIs
- —AI agents that can settle USDC payments on Base
- —Use cases needing keyless, pay-as-you-go API access
Not for
- —Users who need detailed API documentation before integrating
- —High-volume use cases where $0.02/request adds up significantly
- —Anyone without a Base-compatible USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/accounts/57/balance \
-H "X-PAYMENT: <x402-payment-token>" \
-H "Content-Type: application/json"Endpoint
Quality
The endpoint is live and returns a valid x402 challenge, but documentation pages are empty (only 'Connect wallet' prompts). There is no OpenAPI spec, no response schema, and no examples of what the balance endpoint actually returns. The purpose of this specific endpoint (account 57 balance) is unclear.
Warnings
- —All documentation pages (/docs, /pricing, /api, /README) returned no content beyond 'Connect wallet' — no usable docs exist.
- —The specific endpoint path '/api/v1/accounts/57/balance' references a hardcoded account ID (57); it is unclear whether this is a generic resource or a single fixed account.
- —No response schema or example output is available; the data returned after payment is unknown.
- —The platform lists many API categories (AI, finance, analytics, etc.) but none of the doc pages have substantive content, raising questions about actual functionality.
Citations
- —The endpoint returns a 402 x402 challenge with maxAmountRequired of 20000 base units in USDC on Basehttps://lowpaymentfee.com/api/v1/accounts/57/balance
- —USDC asset contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/accounts/57/balance
- —Platform advertises $0.02/request flat pricing with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —Documentation pages return only 'Connect wallet' with no substantive contenthttps://lowpaymentfee.com/docs