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Quartermaster ETH/ERC-20 Balance Checker on Base
x402
Quartermaster ETH/ERC-20 Balance Checker on Base is a paid API for AI agents from quartermaster.surewhynot.app, paid per call via x402, $0.001/call, status unknown (last checked 2026-09-14).
Returns the ETH or ERC-20 (e.g. USDC) token balance of a given wallet address on the Base blockchain for pre-flight funding checks.
Price / call$0.001
Success—
StatusUnknown
How this service works
Check ETH and USDC (or any ERC-20) balance of an address on Base — pre-flight funding checks for payments and settlement.
Output
Returns the token balance (as a numeric amount) for the queried EVM address on Base, for either ETH, USDC (default), or any specified ERC-20 contract address.
Example use cases
Example prompt
“Before sending the payment, check whether wallet 0xAbC1234567890abcdef1234567890abcdef123456 has enough USDC on Base to cover it — look up its USDC balance for me.”
Technical details
Endpoint
GEThttps://quartermaster.surewhynot.app/v1/balanceWhen to prefer
Use this endpoint when you need to verify a wallet's on-chain token balance on Base before executing or approving a payment, particularly in x402 payment workflows. Prefer this over generic block explorers when you need a programmatic, agent-callable balance check with minimal latency.
Side effects
- Invalid or malformed EVM address (not matching 0x + 40 hex chars) returns a validation error
- Unknown or invalid ERC-20 contract address returns an error or zero balance
- Network issues reaching Base RPC return a connectivity error
- Rate limiting or payment failure (x402) if the $0.001 USDC fee is not satisfied
Input
Schema · Request body
| Field | Type | Description |
|---|---|---|
| inputrequired | object | |
| output | object |
Tags
x402
Reviews
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