Build an AI-Powered Token Swap Agent on Celo Using GOAT SDK

​

Understanding GOAT SDK for Token Swapping

​

1. Importing Libraries

import readline from "node:readline";
import { openai } from "@ai-sdk/openai";
import { generateText } from "ai";
import { http } from "viem";
import { createWalletClient } from "viem";
import { privateKeyToAccount } from "viem/accounts";
import { celo } from "viem/chains"; // Using Celo chain
import { getOnChainTools } from "@goat-sdk/adapter-vercel-ai";
import { cUSD, CELO, erc20 } from "@goat-sdk/plugin-erc20"; // Celo tokens
import { uniswap } from "@goat-sdk/plugin-uniswap";
import { sendETH } from "@goat-sdk/wallet-evm";
import { viem } from "@goat-sdk/wallet-viem";
require("dotenv").config();

​

Library Descriptions:

• readline: This Node.js module is used to create an interactive command-line interface, allowing the user to input prompts and interact with the agent.
• @ai-sdk/openai and ai: These libraries facilitate the integration with OpenAI’s models (like gpt-4o-mini) to generate text responses and process natural language prompts.
• viem: A popular Javascript library for interacting with Ethereum-compatible blockchains, including Celo.
• http, createWalletClient, privateKeyToAccount: These are viem modules used to create a wallet client for blockchain interactions.
• celo: This imports the chain configuration for the Celo blockchain.
• @goat-sdk: This SDK provides tools to simplify on-chain interactions for AI agents.
• getOnChainTools: A function to bundle various on-chain tools for the agent.
• @goat-sdk/plugin-erc20, erc20, cUSD, CELO: Modules for handling ERC20 tokens on Celo.
• @goat-sdk/plugin-uniswap, uniswap: Modules for interacting with decentralized exchanges.
• @goat-sdk/wallet-evm, viem: Wallet adapters to connect viem wallet client with @goat-sdk tools.
• dotenv: This library loads environment variables from a .env file.

​

2. Wallet Client Creation

// 1. Create a wallet client
const account = privateKeyToAccount(process.env.WALLET_PRIVATE_KEY as `0x${string}`);

const walletClient = createWalletClient({
    account: account,
    transport: http(process.env.RPC_PROVIDER_URL),
    chain: celo, // Using Celo chain configuration
});

• It retrieves the private key from the WALLET_PRIVATE_KEY environment variable.
• privateKeyToAccount converts the private key into a viem account object.
• createWalletClient initializes a wallet client connected to the Celo blockchain using the RPC URL from the RPC_PROVIDER_URL environment variable.

​

3. Setting Up On-Chain Tools for Token Swapping

// 2. Get your onchain tools for your wallet
const tools = await getOnChainTools({
    wallet: viem(walletClient),
    plugins: [
        sendETH(), // Enable CELO transfers (native token)
        erc20({ tokens: [cUSD, CELO] }), // Enable Celo token operations
        uniswap({
            baseUrl: process.env.UNISWAP_BASE_URL as string,
            apiKey: process.env.UNISWAP_API_KEY as string,
        }),
    ],
});

• wallet: viem(walletClient): Provides the viem wallet client to the toolset.
• plugins: An array of plugins that extend the agent’s capabilities:
  • sendETH(): Enables sending native CELO (although named ETH in the function, it handles the native token).
  • erc20({ tokens: [cUSD, CELO] }): Enables ERC20 token operations for Celo-specific tokens.
  • uniswap(...): Enables interaction with Uniswap, configured with a baseUrl and apiKey from environment variables.

​

4. Command Line Interface and AI Interaction Loop

// 3. Create a readline interface to interact with the agent
const rl = readline.createInterface({
  input: process.stdin,
  output: process.stdout,
});

while (true) {
  const prompt =
    (await new Promise()) <
    string >
    ((resolve) => {
      rl.question('Enter your prompt (or "exit" to quit): ', resolve);
    });

  if (prompt === "exit") {
    rl.close();
    break;
  }

  console.log("\n-------------------\n");
  console.log("TOOLS CALLED");
  console.log("\n-------------------\n");
  try {
    const result = await generateText({
      model: openai("gpt-4o-mini"),
      tools: tools,
      maxSteps: 10, // Maximum number of tool invocations per request
      prompt: prompt,
      onStepFinish: (event) => {
        console.log(event.toolResults);
      },
    });

    console.log("\n-------------------\n");
    console.log("RESPONSE");
    console.log("\n-------------------\n");
    console.log(result.text);
  } catch (error) {
    console.error(error);
  }
  console.log("\n-------------------\n");
}

• The agent accepts commands like “Swap cUSD for CELO” or “Check my token balance”
• generateText() processes these commands through the AI model (gpt-4o-mini)
• The AI determines which tools to call to fulfill the request
• Results are returned in natural language

​

Setting Up Your Celo Token Swap Agent

​

1. Clone the Repository

git clone https://github.com/goat-sdk/goat.git && cd goat

​

2. Install and Build Dependencies

cd typescript
pnpm install
pnpm build

​

3. Navigate to the Example Directory

cd examples/by-use-case/evm-swap-tokens

​

4. Configure Environment Variables

cp .env.template .env

OPENAI_API_KEY=your_openai_api_key
WALLET_PRIVATE_KEY=your_wallet_private_key
RPC_PROVIDER_URL=https://forno.celo.org  # Celo Mainnet
# or use https://forno.celo-sepolia.celo-testnet.org/ for Testnet
UNISWAP_BASE_URL=provided_value  # Will be populated from template
UNISWAP_API_KEY=provided_value   # Will be populated from template

​

5. Run the Interactive CLI

pnpm ts-node index.ts

​

Using the Token Swap Agent on Celo

Swap cUSD for CELO
Swap CELO for cUSD
Check my token balance
What's the current exchange rate between cUSD and CELO?

​

Production Considerations for Token Swap Agents

​

Enhance Security with Programmable Permissions

• Limit fund amounts for transactions
• Restrict contract interactions to trusted protocols
• Define required signatures for high-value transactions

​

Maintain Regulatory Compliance with Non-Custodial Wallets

• Ensure agent platforms never have access to users’ wallets
• Avoid money transmitter license requirements
• Improve user trust and control

​

Celo-Specific Considerations

• Gas Fees: Celo uses CELO as gas for transactions, so ensure your wallet has sufficient CELO.
• Liquidity Sources: Consider using Celo-specific DEXes like Ubeswap or Uniswap.
• Stable Tokens: Celo offers several stable tokens (cUSD, cEUR, cREAL) that might be useful for your swap use cases.

​

Conclusion