# EVM Wallet Balance & x402 Payment Readiness Checker

> EVM Wallet Balance & x402 Payment Readiness Checker is a paid API for AI agents from gpt55.558686.xyz, paid per call via x402, $0.001/call, status unknown (last checked 2026-09-14).

Reads a public EVM wallet's USDC and native gas balance on Base or Ethereum and determines whether it can cover a $0.001 x402 payment, returning a funding-readiness snapshot with runway and shortfall details.

## Facts

- Endpoint: GET https://gpt55.558686.xyz/v1/tools/evm-wallet-balance
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/evm-wallet-balance-x402-payment-readiness-checker-97f1498b
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_qFHjIJ8DvP4YWjjbvMksd

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 evm-wallet-balance-x402-payment-readiness-checker-97f1498b
```

Example prompt: Check whether the wallet 0xAbC1234567890abcdef1234567890abcdef123456 on Base has enough USDC to cover a $0.001 x402 payment — I want to see the balance, any shortfall, and whether gas is present.

## When to prefer this

Use this endpoint when an agent or workflow needs to verify that a specific EVM wallet is funded with enough Base USDC to cover a $0.001 x402 micropayment before attempting the payment — especially in pre-flight checks, funding audits, or automated agent pipelines where signing and broadcasting are handled elsewhere. Prefer this over a general blockchain explorer when you specifically need x402 payment readiness framing with runway and shortfall calculations.

## Known failure modes

- Invalid or malformed wallet address returns a validation error
- Unsupported chain/network value returns an enum error
- RPC or provider timeout may return an upstream error with no balance data
- Wallet with zero USDC returns a shortfall equal to the full payment amount
- Network congestion may cause stale or delayed balance reads

## How this service works

Read a public EVM wallet balance on Base or Ethereum and determine whether its Base USDC balance can cover a suggested $0.001 x402 payment. Returns a coherent provider snapshot, USDC runway, shortfall, native-gas presence, and a handoff to the full funding-readiness doctor without signing, broadcasting, or handling private keys. Balance-only readiness does not prove client, signing, spend-cap, or retry capability. GET variant for agents, crawlers, and wallets that prefer query parameters over...

## Output

Returns a provider snapshot including the wallet's Base USDC balance, native gas presence, USDC runway (how many $0.001 payments can be made), shortfall if the balance is insufficient, overall payment readiness verdict, and a pointer to a full funding-readiness diagnostic. Does not sign transactions, broadcast anything, or touch private keys.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET",
      "HEAD",
      "DELETE"
     ],
     "type": "string"
    },
    "pathParams": {
     "type": "object",
     "additionalProperties": true
    },
    "queryParams": {
     "type": "object",
     "required": [
      "address"
     ],
     "properties": {
      "chain": {
       "enum": [
        "base",
        "ethereum",
        "mainnet",
        "eip155:8453",
        "eip155:1",
        "8453",
        "1"
       ],
       "type": "string"
      },
      "wallet": {
       "type": "string",
       "pattern": "^0x[0-9a-fA-F]{40}$"
      },
      "address": {
       "type": "string",
       "pattern": "^0x[0-9a-fA-F]{40}$"
      },
      "network": {
       "enum": [
        "base",
        "ethereum",
        "mainnet",
        "eip155:8453",
        "eip155:1",
        "8453",
        "1"
       ],
       "type": "string",
       "default": "base"
      }
     },
     "additionalProperties": false
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "additionalProperties": true
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "ok": true,
  "tool": "evmWalletBalance",
  "address": "0x1111111111111111111111111111111111111111",
  "chainId": "eip155:8453",
  "network": "base",
  "observedAt": "2026-08-10T00:00:00.000Z",
  "blockNumber": "1234567",
  "usdcBalance": {
   "raw": "1234567",
   "symbol": "USDC",
   "decimals": 6,
   "formatted": "1.234567",
   "tokenAddress": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913"
  },
  "nativeBalance": {
   "raw": "1000000000000000000",
   "symbol": "ETH",
   "decimals": 18,
   "formatted": "1"
  },
  "x402Readiness": {
   "shortfall": {
    "atomic": "0",
    "formatted": "0"
   },
   "assessment": "balance_ready",
   "balanceOnly": true,
   "limitations": [
    "Balance signals do not prove payment-client, typed-data signing, spend-cap, or same-request retry readiness."
   ],
   "nativeGasPresent": true,
   "suggestedPayment": {
    "asset": "USDC",
    "network": "eip155:8453",
    "amountUsd": "0.001",
    "amountAtomic": "1000"
   },
   "walletNetworkMatches": true,
   "fundingReadinessDoctor": {
    "paidUrl": "https://gpt55.558686.xyz/v1/tools/x402-wallet-funding-readiness-doctor",
    "guideUrl": "https://gpt55.558686.xyz/x402/wallet-funding-readiness-doctor"
   },
   "canCoverSuggestedX402Amount": true,
   "usdcRunwayAtSuggestedAmount": "1234"
  },
  "rpcProviderHost": "rpc.example.test"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/evm-wallet-balance-x402-payment-readiness-checker-97f1498b/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from gpt55.558686.xyz](https://www.zero.xyz/host/gpt55.558686.xyz/llms.txt)