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/25/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 25). There is no OpenAPI schema, no detailed documentation, and no example request/response bodies available from the crawled material. The docs, API, pricing, and README pages all returned only a "Connect wallet" prompt with no substantive content. The endpoint is live and returns a valid x402 challenge, but the actual response format and input parameters beyond the POST method are unknown.
Capabilities
Use cases
- —Querying account balance information via a single paid API call
- —Integrating pay-per-request balance lookups into agent workflows
- —Demonstrating x402 payment protocol usage on Base
Fit
Best for
- —Agents needing on-demand account balance data without subscription commitments
- —Developers experimenting with x402 payment-gated APIs
- —Low-volume balance queries where per-call pricing is economical
Not for
- —High-volume balance polling where per-request fees accumulate quickly
- —Use cases requiring detailed API documentation or guaranteed SLAs
- —Users who need free or API-key-based authentication instead of crypto payments
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/accounts/25/balance
# Returns 402 with x402 challenge; include X-PAYMENT header with valid USDC payment on Base to access.Endpoint
Quality
The endpoint is live and returns a valid x402 challenge, but there is no OpenAPI schema, no documentation, no example requests or responses, and the docs pages are empty. The purpose of this specific endpoint (account 25 balance) is unclear and the broader platform lacks substantive documentation.
Warnings
- —No OpenAPI or schema documentation available for this endpoint
- —All documentation pages (docs, API, pricing, README) returned only a 'Connect wallet' prompt with no content
- —The specific resource '/api/v1/accounts/25/balance' is hardcoded to account ID 25; unclear if this is parameterizable
- —Response format and input parameters are entirely unknown
Citations
- —The x402 challenge requires a maximum of 20,000 base units of USDC (USD Coin) on the Base network, equaling $0.02 per request.https://lowpaymentfee.com/api/v1/accounts/25/balance
- —The provider advertises $0.02/request pricing with no API keys, no rate limits, and instant access on the Base network.https://lowpaymentfee.com
- —The provider offers APIs across data & analytics, AI/ML, finance & Web3, and infrastructure categories.https://lowpaymentfee.com