x402-gated account balance endpoint on Base, pay-per-call with USDC.
What it does
This endpoint at lowpaymentfee.com provides a "Premium API Access" account balance resource at `/api/v1/accounts/67/balance`. It is part of a broader platform (lowpaymentfee.com) that offers a variety of x402-gated APIs spanning data & analytics, AI & machine learning, finance & Web3, and infrastructure utilities — all priced at $0.02 per request and settled in USDC on the Base network.
The specific endpoint probed here advertises a maximum payment of 20,000 base units of USDC (asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Base). Since USDC uses 6 decimals, this equates to $0.02 per call. Payment is made via the x402 protocol's "exact" scheme: callers include an X-PAYMENT header with a signed payment authorization, and the endpoint returns JSON. No API keys or rate limits are advertised; access is purely pay-per-request.
The endpoint is live and returns a proper 402 challenge. However, documentation is extremely sparse — the docs, pricing, API, and README pages all render only a "Connect wallet" prompt with no further technical detail. There is no OpenAPI schema, no request/response examples, and no description of what the "balance" resource actually returns or what input parameters it expects. The endpoint accepts POST requests based on the outputSchema. The platform appears to be a demonstration or early-stage x402 API marketplace.
Capabilities
Use cases
- —Querying account balance information via a pay-per-request model without API keys
- —Demonstrating x402 protocol payment flows on Base with USDC
- —Integrating low-cost per-call APIs into agent workflows that settle payments on-chain
Fit
Best for
- —Developers experimenting with x402 payment protocol integrations
- —Agents that need keyless, pay-per-call API access on Base
- —Projects requiring on-chain USDC micropayments for API consumption
Not for
- —Production workloads requiring well-documented, stable APIs with SLAs
- —Users who need detailed request/response schemas before integration
- —High-volume use cases where per-request crypto settlement overhead is impractical
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/accounts/67/balance
# Returns 402 with x402 challenge. Include X-PAYMENT header with signed USDC payment on Base to access.Endpoint
Quality
The endpoint is live and returns a valid x402 402 challenge, confirming it exists and accepts payments. However, there is no OpenAPI schema, no documentation beyond a wallet-connect prompt, no request/response examples, and no explanation of what the balance endpoint actually returns. The listing is effectively a stub with confirmed liveness.
Warnings
- —No documentation available — docs, pricing, API, and README pages all show only 'Connect wallet'
- —No OpenAPI or request/response schema provided; input parameters and response format are unknown
- —The specific purpose of /api/v1/accounts/67/balance is unclear — 'Premium API Access' is a generic label
- —Platform may be a demo or early-stage project; reliability and longevity are uncertain
Citations
- —The endpoint returns a 402 challenge with x402Version 1, exact scheme, USDC on Base, maxAmountRequired 20000https://lowpaymentfee.com/api/v1/accounts/67/balance
- —The platform advertises $0.02 per request pricing with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —USDC asset address on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/accounts/67/balance
- —Docs, pricing, API, and README pages render only 'Connect wallet' with no further contenthttps://lowpaymentfee.com/docs