x402-gated account balance endpoint on Base, pay $0.02 per request in USDC.
What it does
This endpoint at lowpaymentfee.com provides a "Premium API Access" account balance query via the x402 payment protocol. It is part of a broader platform that offers dozens of pay-per-call API endpoints spanning data analytics, AI/ML inference, finance/Web3 data, and infrastructure utilities — all priced at $0.02 per request, settled in USDC on the Base network.
The specific endpoint `/api/v1/accounts/60/balance` accepts POST requests and returns JSON. Payment is handled inline via the x402 protocol: callers attach an `X-PAYMENT` header containing a signed USDC payment of up to 20,000 base units (i.e., $0.02, since USDC uses 6 decimals). The payment is sent to address `0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3` on Base mainnet, with a 300-second timeout window. No API keys or rate limits are advertised; access is purely payment-gated.
Documentation is extremely sparse — the docs, pricing, and API pages all render only a "Connect wallet" prompt with no further content. There is no OpenAPI schema, no request/response examples, and no explanation of what "accounts/60/balance" actually returns or what parameters it accepts. The platform appears to be a demonstration or early-stage deployment of x402-powered APIs. The endpoint is confirmed live (returns a valid 402 challenge), but the lack of documentation makes it difficult to use without experimentation.
Capabilities
Use cases
- —Querying account balance data with per-request USDC micropayments
- —Integrating x402 payment-gated endpoints into agent workflows
- —Testing x402 protocol implementations against a live endpoint
Fit
Best for
- —Developers experimenting with x402 payment protocol
- —Agents that can sign USDC transactions on Base
- —Low-cost per-request API access without API key management
Not for
- —Production use requiring documented request/response schemas
- —Users who need fiat payment options or cannot transact on Base
- —High-throughput batch queries where per-call payment overhead is impractical
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/accounts/60/balance \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <signed-x402-payment-header>"Endpoint
Quality
The endpoint is live and returns a valid x402 402 challenge, confirming it works. However, there is no OpenAPI schema, no request/response examples, and no meaningful documentation beyond a landing page listing endpoints. The specific purpose of 'accounts/60/balance' is unexplained. This is effectively a stub listing.
Warnings
- —No documentation available — docs, pricing, and API pages all show only 'Connect wallet' with no content
- —No OpenAPI or schema describing request parameters or response format
- —The meaning of 'accounts/60/balance' (what account 60 is, what balance is returned) is completely undocumented
- —Platform appears to be early-stage or a demo; reliability and longevity are unknown
Citations
- —Endpoint returns a valid x402 402 challenge with maxAmountRequired of 20000 base units in USDC on Basehttps://lowpaymentfee.com/api/v1/accounts/60/balance
- —Platform advertises $0.02 per request pricing with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —USDC asset contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/accounts/60/balance
- —Docs, pricing, and API pages render only 'Connect wallet' with no additional contenthttps://lowpaymentfee.com/docs