Query UNI token wallet balances via x402 micropayment on Base for $0.02 per request.
What it does
This endpoint at lowpaymentfee.com returns wallet balance information for the UNI (Uniswap) token. It is part of a broader suite of pay-per-call APIs offered by the same provider, spanning data analytics, AI/ML inference, finance/Web3, and utility services. All endpoints on the platform use the x402 payment protocol, settling in USDC on the Base network.
The specific endpoint `/api/v1/wallet/UNI/balance` accepts POST requests and costs $0.02 per call (20,000 base units of USDC with 6 decimals). Payment is made via the x402 `X-PAYMENT` header using the "exact" scheme. There are no API keys, no rate limits, and no signup required — access is granted instantly upon valid payment. The payment recipient address is `0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3`, and the payment asset is USDC at contract `0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913` on Base.
Documentation on the site is extremely sparse — the docs, API, pricing, and README pages all render only a "Connect wallet" prompt with no additional technical detail. There is no OpenAPI schema, no request/response examples, and no description of what parameters the POST body expects or what the response payload looks like. The endpoint is confirmed live (returns 402 challenge), but the actual functionality and response format must be inferred from the URL path alone.
Capabilities
Use cases
- —Checking UNI token balance for a given wallet address
- —Portfolio tracking applications that need on-demand balance lookups
- —Automated trading bots verifying UNI holdings before executing trades
- —DeFi dashboards displaying real-time token balances
Fit
Best for
- —Agents or apps needing on-demand UNI balance queries without API key management
- —Low-volume, pay-as-you-go crypto balance lookups
- —x402-native workflows that settle payments in USDC on Base
Not for
- —High-frequency balance polling where per-request costs add up quickly
- —Users who need detailed transaction history or multi-token batch queries
- —Anyone requiring comprehensive documentation or SLA guarantees
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/wallet/UNI/balance \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402_payment_token>" \
-d '{"address": "0xYourWalletAddress"}'Example
Request
{
"address": "0x1234567890abcdef1234567890abcdef12345678"
}Endpoint
Quality
The endpoint is confirmed live via a valid 402 challenge, and pricing is clear ($0.02 USDC on Base). However, there is no OpenAPI schema, no documentation, no request/response examples, and the docs pages are empty. The actual request parameters and response format are entirely unknown and had to be guessed from the URL path.
Warnings
- —No documentation available — docs, API, pricing, and README pages all show only 'Connect wallet' with no content.
- —No OpenAPI or JSON schema describing request parameters or response format.
- —Example request JSON is inferred from the URL path and is not confirmed by any documentation.
- —The broader platform lists many endpoint categories but provides no technical detail for any of them.
Citations
- —Endpoint returns 402 with x402 challenge, confirming it is livehttps://lowpaymentfee.com/api/v1/wallet/UNI/balance
- —Price is $0.02 per request (20000 base units USDC, 6 decimals) on Base networkhttps://lowpaymentfee.com
- —Payment asset is USDC at contract 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/wallet/UNI/balance
- —No API keys, no rate limits, instant access advertisedhttps://lowpaymentfee.com
- —Docs, API, pricing, and README pages render only 'Connect wallet'https://lowpaymentfee.com/docs