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/172/balance` is gated behind a per-request USDC payment on the Base network. The x402 challenge confirms the endpoint is live and accepts POST requests, returning JSON responses.
The parent site lowpaymentfee.com hosts a broader suite of pay-per-call 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 $0.02 per request with no API keys, no rate limits, and no commitments required. Payment settles in USDC on the Base L2 network.
The probed endpoint charges a maximum of 20,000 base units of USDC (6 decimals), which equals $0.02 per call. The x402 challenge specifies the "exact" payment scheme, a 300-second timeout, and pays to address 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3. Documentation on the site is extremely sparse — the docs, API, pricing, and README pages all render only a "Connect wallet" prompt with no further content. The actual response schema and input parameters for this specific balance endpoint are undocumented.
Capabilities
Use cases
- —Querying account balance information via a single paid API call
- —Integrating pay-per-request balance lookups into agent workflows
- —Demonstrating x402 protocol payment flows on Base network
Fit
Best for
- —Agents needing on-demand account balance data without subscription commitments
- —Developers experimenting with x402 payment protocol integrations
- —Low-volume, pay-as-you-go API consumption on Base
Not for
- —High-volume balance queries where per-call fees add up quickly
- —Users who need detailed API documentation or guaranteed SLAs
- —Anyone without USDC on the Base network
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/accounts/172/balance \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is live (402 challenge confirmed) and pricing is clear ($0.02/call in USDC on Base). However, there is no documentation for the balance endpoint's input parameters or response schema, no OpenAPI spec, and all doc pages render only 'Connect wallet'. The specific purpose of account 172's balance is unknown.
Warnings
- —No API documentation available — all doc pages show only 'Connect wallet'
- —No OpenAPI or schema describing request parameters or response format for this endpoint
- —The specific meaning of 'accounts/172/balance' is undocumented — unclear what account 172 represents
- —No examples of successful responses are available
Citations
- —The endpoint returns a 402 x402 challenge with maxAmountRequired of 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/accounts/172/balance
- —All endpoints are priced at $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —The site offers APIs across data & analytics, AI/ML, finance & Web3, and infrastructure categorieshttps://lowpaymentfee.com
- —USDC asset address is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/accounts/172/balance