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How to Check Base Chain Wallet Balance with an AI Agent

Base is Coinbase's Ethereum L2 — the chain that brought millions of everyday users onchain. From social tokens on Farcaster to consumer crypto startups and Coinbase Wallet integrations, Base is where retail-scale blockchain activity happens. Build an AI agent to monitor ETH balances on Base, track app treasury wallets, and stay ahead of onchain consumer trends.

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 Base RPC endpoint — no separate account needed (included in the config below)
• A text editor — nothing else

---

Create the Project Folder

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

The Skill Files

SKILL.md

---
name: base-agent
description: Check ETH balance on Base L2
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 on the Base network.
Report the address and ETH balance. Nothing else.

agent.yaml

name: Base Agent
description: Check ETH balance on Base L2
connectors:
  - connection_name: Base
    connection_type: web3
skills:
  - path: ./
    trigger_type: auto

The Config File

Base uses ETH as its native token. The base.publicnode.com endpoint connects directly to the Base L2 network — free, fast, and no signup required:

{
  "llm": {
    "provider": "openai",
    "model": "gpt-4o",
    "apiKey": "sk-..."
  },
  "server": {
    "enabled": false,
    "port": 3333,
    "apiKey": "your-secret-api-key"
  },
  "connectors": [
    {
      "connection_name": "Base",
      "connection_type": "web3",
      "baseUrl": "https://base.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 ./base-agent

2 Windows

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

3 macOS

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

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

4 Linux

chmod +x oe-runtime-linux
./oe-runtime-linux ./base-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": {}}'

Consumer Crypto Use Cases on Base

• Onchain app treasury monitoring — Consumer apps built on Base — social platforms, creator tools, gaming apps — hold ETH in treasury wallets for gas subsidies and user reward pools. Monitor these wallets to ensure operational reserves stay healthy and alert when they need topping up.
• Social token creator tracking — Base is home to creator economies on Farcaster and friend.tech-style social apps. Track the ETH balances of creator wallets to gauge their financial activity and creator income from token launches and social engagement rewards.
• Coinbase Wallet integration auditing — Products that deeply integrate with Coinbase Wallet need to monitor the Base wallet balances of their most active users (with consent) to personalise UX and detect when users are running low on gas before a critical in-app transaction fails.
• Consumer startup fundraising tracking — Consumer crypto startups frequently raise onchain via token sales on Base. Monitor multi-sig treasury wallets of portfolio companies and track ETH movements to flag unusual spending or large withdrawals that fall outside approved budgets.
• NFT mint wallet monitoring — NFT projects on Base need funded wallets for deploying contracts and covering gas during mint events. Track deployer wallet balances and alert before they fall below the minimum needed for a safe collection launch.
• Loyalty reward pool auditing — Consumer brands experimenting with onchain loyalty programs hold ETH and ERC-20s on Base. Audit reward pool wallet balances weekly to confirm programme liability matches available assets.