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How to Check Ethereum Wallet Balance with an AI Agent

Ethereum holds more value than any other blockchain. Query wallet balances, audit DeFi positions, and surface on-chain intelligence from any Ethereum address — using plain English, two config files, and one command. No cloud platform required.

What You Need

• Node.js 18+ installed, or the OE Runtime binary from openenthrium.com/runtime
• An API key from OpenAI, Anthropic, or any supported LLM provider
• A free public Ethereum RPC endpoint — no separate account needed (included in the config below)
• A text editor — nothing else

---

Create the Project Folder

Create a folder called ethereum-agent/ and add these two files:

The Skill Files

SKILL.md

---
name: ethereum-agent
description: Check Ethereum wallet balance
license: Apache-2.0
metadata:
  author: Open Enthrium
  version: "1.0"
---

You are a blockchain data agent. Use the tools to fetch data and respond concisely.

## Step 1: Check Balance
Get the ETH balance for the configured wallet address.
Report the address and balance in ETH. Nothing else.

agent.yaml

name: Ethereum Agent
description: Check Ethereum wallet balance
connectors:
  - connection_name: Ethereum
    connection_type: web3
skills:
  - path: ./
    trigger_type: auto

The Config File

Create oe-config.json in the same folder. ethereum.publicnode.com is a free, no-API-key Ethereum RPC endpoint:

{
  "llm": {
    "provider": "openai",
    "model": "gpt-4o",
    "apiKey": "sk-..."
  },
  "server": {
    "enabled": false,
    "port": 3333,
    "apiKey": "your-secret-api-key"
  },
  "connectors": [
    {
      "connection_name": "Ethereum",
      "connection_type": "web3",
      "baseUrl": "https://ethereum.publicnode.com",
      "walletAddress": "0xYOUR_WALLET_ADDRESS"
    }
  ]
}

Download OE Runtime

Run the Agent

From the parent folder containing your skill directory:

	Method	Best for	Download
1	npx recommended	No install needed — always runs the latest version	—
2	Windows .exe	Download once, run offline on Windows	⊞ Windows (.exe)
3	macOS binary	Download once, run offline on Mac	 macOS
4	Linux binary	Server deployments, cron jobs, Docker	🐧 Linux
5	API Server integration	Call from any app, webhook, or automation pipeline	📮 Postman Collection

1 npx recommended

npx -y @openenthrium/oe-runtime@latest ./ethereum-agent

2 Windows

oe-runtime-win.exe ./ethereum-agent

3 macOS

chmod +x oe-runtime-macos
./oe-runtime-macos ./ethereum-agent

First run blocked? System Settings → Privacy & Security → Allow Anyway.

4 Linux

chmod +x oe-runtime-linux
./oe-runtime-linux ./ethereum-agent

5 API Server integration

Add a "server" block to oe-config.json, then start with --serve:

{
  "llm": { ... },
  "server": { "enabled": true, "port": 3333, "apiKey": "your-secret-key" },
  "connectors": [ ... ]
}

npx -y @openenthrium/oe-runtime@latest --serve --config oe-config.json

Run with inline YAML:

curl -X POST http://localhost:3333/run \
  -H "Content-Type: application/json" \
  -H "X-API-Key: your-secret-key" \
  -d '{"yaml": "...", "params": {}}'

Or run from a file on the server:

curl -X POST http://localhost:3333/run-file \
  -H "Content-Type: application/json" \
  -H "X-API-Key: your-secret-key" \
  -d '{"file": "/path/to/agent.yaml", "params": {}}'

What You Get Back

The agent calls the Ethereum RPC, converts the raw wei balance to ETH, and returns a plain-English response:

Address: 0xYOUR_WALLET_ADDRESS
Balance: 6.635339 ETH

Enterprise Use Cases

• Compliance wallet auditing — Periodically verify that company or custodial Ethereum wallets hold expected balances. Flag unexpected outflows for immediate review without accessing a third-party dashboard.
• DeFi position monitoring — Track the ETH balance across multiple wallets interacting with Uniswap, Aave, or Compound. Surface undercollateralised positions before they become liquidation risks.
• DAO treasury reporting — Generate weekly balance reports for Ethereum-based DAO treasuries and multisig wallets. Deliver summaries to stakeholders without manual on-chain lookups.
• Counterparty due diligence — Before entering a token deal or DeFi protocol interaction, verify the counterparty's Ethereum wallet history and current holdings. Surface wallet age, balance patterns, and interaction with flagged contracts.
• Smart contract treasury tracking — Monitor the ETH held in deployed smart contracts — escrow contracts, vesting contracts, or protocol fee collectors — and alert when balances cross defined thresholds.
• Transaction forensics — Trace outgoing ETH flows across wallet hops to reconstruct payment paths. Produce chain-of-custody documentation for compliance or legal review.