Query INJ wallet balance via x402 micropayment on Base for $0.02 per request.
What it does
This endpoint at lowpaymentfee.com returns the wallet balance for the INJ (Injective) token. It is part of a broader suite of pay-per-call APIs offered by lowpaymentfee.com, spanning data analytics, AI/ML inference, finance/Web3, and utility services. All endpoints use the x402 protocol, settling payments in USDC on the Base network.
The specific endpoint `/api/v1/wallet/INJ/balance` accepts POST requests and costs $0.02 per call (20,000 base units of USDC with 6 decimals). No API keys or accounts are required — callers simply attach an x402 payment header with each request. The provider advertises no rate limits and instant access. The x402 challenge was successfully captured, confirming the endpoint is live.
Documentation beyond the landing page 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 should contain or what the response looks like. The endpoint's behavior must be inferred entirely from its URL path and the x402 challenge metadata.
Capabilities
Use cases
- —Checking the balance of an INJ (Injective) wallet address programmatically
- —Building portfolio trackers that need real-time token balances
- —Automating wallet monitoring for INJ holdings without managing API keys
Fit
Best for
- —Agents or apps that need on-demand INJ wallet balance lookups
- —Developers who prefer pay-per-call pricing over subscription API keys
- —x402-compatible agents settling micropayments in USDC on Base
Not for
- —High-volume balance polling where $0.02/request adds up quickly
- —Users who need detailed transaction history or multi-token queries in a single call
- —Anyone requiring comprehensive documentation or guaranteed SLAs
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/wallet/INJ/balance \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402_payment_token>" \
-d '{"address": "inj1..."}'Example
Request
{
"address": "inj1exampleaddress123"
}Endpoint
Quality
The endpoint is live (402 challenge captured) and pricing is clear ($0.02 USDC on Base). However, there is no OpenAPI schema, no request/response documentation, and no examples. The docs pages are empty beyond a wallet-connect prompt. The request body schema and response format are entirely inferred from the URL path.
Warnings
- —No documentation available — docs, API, pricing, and README pages all show only 'Connect wallet'
- —Request body schema is unknown; the example_request_json is speculative based on the URL path
- —Response format is completely undocumented
- —No OpenAPI or machine-readable schema provided
Citations
- —Endpoint returns 402 with x402 challenge advertising USDC on Base network at 20000 base unitshttps://lowpaymentfee.com/api/v1/wallet/INJ/balance
- —All APIs priced at $0.02 per request with no API keys, no rate limits, instant access on Base networkhttps://lowpaymentfee.com
- —USDC asset address 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/wallet/INJ/balance