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/75/balance` is described as "Premium API Access" and returns JSON data when a valid x402 payment header is supplied. Payment is settled in USDC on the Base network using the "exact" scheme, with a maximum cost of $0.02 per request (20,000 base units of USDC at 6 decimals).
lowpaymentfee.com hosts a broader suite of x402-gated APIs spanning data & analytics (metrics, reports, data export, insights), AI & machine learning (sentiment analysis, text summarization, classification, embeddings), finance & Web3 (price feeds, exchange rates, token quotes, gas estimates), and infrastructure utilities (geocoding, validation, conversion, generation). All endpoints are listed at $0.02 per request with no API keys, no rate limits, and no minimum commitments required. The site advertises instant access via the Base network.
Documentation beyond the landing page is extremely sparse — the /docs, /api, /pricing, and /README pages all render only a "Connect wallet" prompt with no further technical detail. There is no OpenAPI spec, no request/response schema documentation, and no usage examples available from the crawl. The endpoint is confirmed live (returns a proper 402 x402 challenge), but the actual response format and input parameters for this specific balance endpoint are unknown.
Capabilities
Use cases
- —Querying account balance data with per-call USDC micropayments
- —Integrating x402-compatible payment flows into agent workflows
- —Accessing financial data without traditional API key management
Fit
Best for
- —Agents or services that already support x402 payment protocol
- —Developers wanting keyless, pay-per-use API access on Base
- —Low-volume or sporadic queries where subscription pricing is wasteful
Not for
- —High-volume use cases where $0.02/request adds up significantly
- —Users who need detailed API documentation or SDKs before integrating
- —Anyone without a Base-compatible USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/accounts/75/balance \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-header>"Endpoint
Quality
The endpoint is confirmed live via a valid 402 x402 challenge, and pricing is clear ($0.02 USDC on Base). However, there is no OpenAPI spec, no request/response schema, no documentation beyond a wallet-connect prompt, and no examples. The purpose of this specific endpoint (account 75 balance) is opaque. Effectively a stub listing.
Warnings
- —No API documentation available — /docs, /api, /pricing, and /README pages all show only 'Connect wallet'
- —No OpenAPI or schema definition found for request or response formats
- —The specific meaning of 'accounts/75/balance' is undocumented — unclear what account 75 refers to
- —The broader site lists many endpoints but none have documented input/output schemas
Citations
- —Endpoint returns 402 with x402 challenge requiring USDC payment on Base networkhttps://lowpaymentfee.com/api/v1/accounts/75/balance
- —maxAmountRequired is 20000 base units of USDC (asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913), equaling $0.02https://lowpaymentfee.com/api/v1/accounts/75/balance
- —Site advertises $0.02/request pricing with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —Documentation pages (/docs, /api, /pricing, /README) render only a 'Connect wallet' prompthttps://lowpaymentfee.com/docs