Check account balance via x402 micropayment on Base network for $0.02 per request.
What it does
This endpoint at lowpaymentfee.com returns account balance information for a specific account (account ID 157) behind an x402 paywall. It is part of a broader platform offering numerous pay-per-call API endpoints across data analytics, AI/ML, finance/Web3, and infrastructure categories, all priced at $0.02 per request and settled in USDC on the Base network.
The endpoint accepts POST requests and returns JSON. Payment is handled via the x402 protocol: callers must include an X-PAYMENT header with a valid payment proof. The x402 challenge specifies an exact-scheme payment of up to 20,000 base units of USDC (0x8335…2913 on Base), which equals $0.02 given USDC's 6 decimals. No API keys or rate limits are advertised; access is gated purely by micropayment.
Documentation is extremely sparse. The landing page lists available endpoints and pricing, but the /docs, /pricing, /api, and /README pages all render only a "Connect wallet" prompt with no substantive content. There is no OpenAPI schema, no request/response examples, and no detailed description of what the balance response contains. The endpoint is live (returns a proper 402 challenge), but the actual functionality and response format must be inferred from the endpoint path alone.
Capabilities
Use cases
- —Querying account balance data for account 157 via a single micropayment
- —Integrating pay-per-call balance checks into agent workflows without API key management
- —Demonstrating x402 protocol micropayment flows on Base network
Fit
Best for
- —Developers experimenting with x402 micropayment protocol
- —Agents needing on-demand account balance lookups without subscription commitments
- —Projects requiring keyless, pay-per-use API access on Base
Not for
- —Production use cases requiring documented response schemas and SLAs
- —Bulk or high-frequency balance queries where per-request pricing is inefficient
- —Users who need fiat payment options (only USDC on Base is accepted)
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/accounts/157/balance \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-proof>"Endpoint
Quality
The endpoint is live and returns a valid x402 402 challenge, confirming it is operational. However, there is no OpenAPI schema, no request/response examples, and all documentation pages render only a wallet-connect prompt. The actual response format and functionality are entirely unknown beyond the path name. This is effectively a stub listing.
Warnings
- —No documentation available — /docs, /pricing, /api, and /README all show only 'Connect wallet' with no content
- —No OpenAPI or schema definition; request body and response format are completely unknown
- —The specific endpoint path (/accounts/157/balance) suggests a hardcoded account ID — unclear if this is a demo or a real resource
- —Platform lists many endpoints but none appear to have public documentation
Citations
- —The endpoint returns a 402 x402 challenge with maxAmountRequired of 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/accounts/157/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 USDC asset address is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/accounts/157/balance