# Base Wallet Snapshot – ETH, USDC, Nonce & Gas Check

> Base Wallet Snapshot – ETH, USDC, Nonce & Gas Check is a paid API for AI agents from kr-x402-mvp.kgy5612.workers.dev, paid per call via x402, $0.003/call, status unknown (last checked 2026-10-31).

Returns a one-call snapshot of a Base wallet: native ETH balance, USDC balance, nonce, live ERC-20 transfer gas cost, and boolean flags indicating whether the wallet can pay gas and x402 micropayments.

## Facts

- Endpoint: GET https://kr-x402-mvp.kgy5612.workers.dev/crypto/wallet-snapshot?utm_source=zero.xyz
- Price: $0.003/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-31
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/base-wallet-snapshot-eth-usdc-nonce-gas-check-1d121202
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_-FrvvL6oBdmapR0XPlzMd

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability base-wallet-snapshot-eth-usdc-nonce-gas-check-1d121202
```

Example prompt: Before I send the USDC payment, can you do a quick wallet snapshot on 0xe4be4d0bd82d8e68203deff81f79ede0529f2617 and tell me if it has enough ETH for gas and enough USDC to cover the x402 fee?

## When to prefer this

Choose this endpoint when you need a combined ETH balance + USDC balance + nonce + gas cost check for a Base wallet in a single call. It is cheaper ($0.003) than calling separate eth-balance, erc20-balance, and gas oracle endpoints individually (which would cost $0.006+). Ideal for agent self-checks before executing on-chain actions, or for verifying a payee wallet is funded before initiating a transfer. Not suitable if you need balances on chains other than Base, or need detailed ERC-20 token lists beyond USDC.

## Known failure modes

- Invalid or malformed wallet address (not matching ^0x[0-9a-fA-F]{40}$) returns a 400 error
- Wallet address not found on Base returns zero balances (valid response, not an error)
- RPC or node timeout may cause delayed or failed responses
- Payment not sent or insufficient x402 payment returns 402 before data is served
- Network congestion may cause gas cost estimates to be stale by seconds

## How this service works

One-call Base wallet quick check (agent self-check or counterparty/payee check before you pay): native ETH + nonce + USDC balance + live gas cost of an ERC-20 transfer, and can_pay_gas / can_pay_x402 booleans. Cheaper than eth-balance + erc20-balance + base-gas separately ($0.006). wallet=0x..

## Output

A JSON object containing: ETH native balance, USDC token balance, chain (always 'base'), account nonce, live gas cost in ETH for a standard ERC-20 transfer, a can_pay_gas boolean (true if ETH covers gas), and a can_pay_x402 boolean (true if USDC balance covers the x402 fee). All values are current at time of call.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "wallet"
     ],
     "properties": {
      "wallet": {
       "type": "string",
       "pattern": "^0x[0-9a-fA-F]{40}$",
       "examples": [
        "0xe4be4d0bd82d8e68203deff81f79ede0529f2617"
       ],
       "description": "Wallet"
      }
     },
     "additionalProperties": false
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "eth": 0,
  "usdc": 0.079,
  "chain": "base",
  "nonce": 0,
  "wallet": "0xe4be4d0bd82d8e68203deff81f79ede0529f2617",
  "can_pay_gas": false,
  "can_pay_x402": true,
  "gas_cost_erc20_transfer_eth": 4e-7
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/base-wallet-snapshot-eth-usdc-nonce-gas-check-1d121202/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from kr-x402-mvp.kgy5612.workers.dev](https://www.zero.xyz/host/kr-x402-mvp.kgy5612.workers.dev/llms.txt)