x402-gated account balance endpoint on Base, pay-per-call with USDC.
What it does
This endpoint at lowpaymentfee.com provides a pay-per-request "Premium API Access" resource at the path /api/v1/accounts/141/balance. It is part of a broader platform (lowpaymentfee.com) that offers a variety of x402-gated APIs spanning data analytics, AI/ML inference, finance/Web3 data, and utility services — all priced at $0.02 per request and settled in USDC on the Base network.
The specific endpoint probed here returns an x402 challenge requesting up to 20,000 base units of USDC (0x8335…2913 on Base, 6 decimals), which equals $0.02 per call. Payment is made via the x402 "exact" scheme: the caller includes an X-PAYMENT header with a signed payment authorization, and the server fulfills the request and returns an application/json response. No API keys, rate limits, or upfront commitments are required.
The endpoint's purpose — "account balance" — is not further documented in the crawled material. The docs, pricing, and API pages all render only a wallet-connect prompt with no additional technical documentation. Without request/response schema details or usage examples, the exact input parameters and output format remain unknown. The platform appears live and functional based on the 402 challenge and the 200 status on the root page, but documentation is essentially absent.
Capabilities
Use cases
- —Querying account balance data 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
- —Developers experimenting with x402 payment protocol
- —Agents that need on-demand account balance data without API key management
- —Low-volume, pay-as-you-go API consumption
Not for
- —Users needing detailed API documentation or schema guarantees before integrating
- —High-volume batch queries where per-request pricing is inefficient
- —Users who cannot transact in USDC on the Base network
Quick start
# 1. Probe the endpoint to get the x402 challenge
curl -X POST https://lowpaymentfee.com/api/v1/accounts/141/balance
# Returns 402 with x402 payment challenge
# 2. Sign and attach payment per x402 spec, then:
curl -X POST https://lowpaymentfee.com/api/v1/accounts/141/balance \
-H "X-PAYMENT: <signed-payment-token>" \
-H "Content-Type: application/json"Endpoint
Quality
The endpoint is live (402 challenge confirmed) and pricing is clear ($0.02 USDC on Base), but there is no documentation, no request/response schema, and the purpose of 'account balance' for account 141 is unexplained. Docs pages render only a wallet-connect prompt. This is effectively a stub listing.
Warnings
- —No API documentation available — docs, pricing, and API pages all render only a wallet-connect prompt with no technical content.
- —The purpose and expected input/output of /api/v1/accounts/141/balance is undocumented; 'Premium API Access' is a generic label applied across the platform.
- —No OpenAPI spec, no request schema, and no response schema were discovered.
- —The endpoint path references a specific account ID (141), which may not be generally useful to arbitrary callers.
Citations
- —The endpoint returns a 402 challenge with x402Version 1, requesting up to 20,000 base units of USDC on Base.https://lowpaymentfee.com/api/v1/accounts/141/balance
- —USDC asset address on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913.https://lowpaymentfee.com/api/v1/accounts/141/balance
- —The platform advertises $0.02 per request, no API keys, no rate limits, instant access, Base network.https://lowpaymentfee.com
- —The platform offers APIs across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categories.https://lowpaymentfee.com