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/89/balance` is gated behind a per-request USDC payment on the Base network. The x402 challenge indicates a maximum cost of 20,000 base units of USDC (0.02 USD per request), consistent with the provider's site-wide pricing of $0.02/request.
The provider, lowpaymentfee.com, hosts a broader suite of x402-gated APIs spanning data & analytics, AI/ML inference (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 the same $0.02/request price point with no API keys, no rate limits, and instant access via the Base network.
This particular endpoint appears to be an account balance query (account ID 89). There is no OpenAPI schema, no request/response documentation, and no usage examples available from the crawled pages. The docs, API, pricing, and README pages all returned only a "Connect wallet" prompt with no substantive content. The endpoint is confirmed live via a valid 402 challenge, but the actual response format and required POST body are unknown.
Capabilities
Use cases
- —Querying account balance information via a single paid API call
- —Integrating pay-per-use balance lookups into agent workflows
- —Accessing financial account data without API key registration
Fit
Best for
- —Agents needing on-demand account balance data without subscription commitments
- —Developers testing x402 payment protocol integrations
- —Low-volume balance queries where per-call pricing is economical
Not for
- —High-volume balance polling where per-request fees would accumulate quickly
- —Use cases requiring detailed API documentation or guaranteed SLAs
- —Users who cannot transact in USDC on the Base network
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/accounts/89/balance
# Returns 402 with x402 challenge; attach X-PAYMENT header with USDC payment proof on Base to access.Endpoint
Quality
The endpoint is confirmed live via a valid 402 challenge, but there is no documentation, no OpenAPI schema, no request/response examples, and no explanation of what 'account 89 balance' actually returns. The docs pages are empty beyond a wallet connect prompt. This is effectively a stub listing.
Warnings
- —No API documentation available — docs, pricing, and README pages all show only 'Connect wallet' with no content.
- —No request body schema or response schema documented; the POST body format is unknown.
- —The specific resource '/api/v1/accounts/89/balance' is hardcoded to account ID 89 — unclear if this is parameterizable or a fixed demo endpoint.
- —The broader lowpaymentfee.com platform lists many endpoints but none have visible documentation beyond titles and prices.
Citations
- —The x402 challenge returns maxAmountRequired of 20000 base units of USDC (USD Coin) on the Base networkhttps://lowpaymentfee.com/api/v1/accounts/89/balance
- —Site-wide pricing is $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —The provider offers APIs across data & analytics, AI/ML, finance & Web3, and infrastructure categorieshttps://lowpaymentfee.com