MonDeployer - Monad Contract Deployment Tool

This repository provides tools for compiling and deploying Solidity contracts to the Monad testnet.

⚠️ Solidity Version Note

Use Solidity 0.8.x & up only. Monad is compatible with standard EVM 0.8.x series. For best results, keep your contracts simple and tested.

🛠 Getting Started

1. Create a file named env.js in the root directory and add your private key like this:

// env.js
exports.PRIVATE_KEY = 'your_private_key_here';

2. Write your contract using the correct pragma:

// SPDX-License-Identifier: MIT
pragma solidity 0.8.28;

contract YourContract {
  // ...
}

🔧 Solution to JSON Parsing Errors

If you see errors like:

MCP monad-mcp: Unexpected token 'L', "Looking fo"... is not valid JSON
MCP monad-mcp: Unexpected token 'D', "Deploying "... is not valid JSON
MCP monad-mcp: Unexpected token 'M', "Monad MCP "... is not valid JSON

We have multiple solutions for you:

1. Ultra-Simple Mock MCP Plugin (Most Reliable)

For fastest debugging, use our ultra-simple MCP plugin that always returns a mock success:

npm run start-simple-mcp

This plugin ignores your contract and always returns a successful deployment response.

🧠 Claude MCP Integration

{
  "mcpServers": {
    "monad-mcp": {
      "command": "node",
      "args": [
        "/path/to/yourfiles/monad-mcp/multi-tool-plugin-v2.cjs"
      ]
    }
  }
}

To start the MCP server manually:

cd monad-mcp && node multi-tool-plugin-v2.cjs

2. Strict MCP Plugin (Auto-Fixes Solidity Version)

For actual contract deployment with version auto-fixing:

npm run start-strict-mcp

This plugin automatically fixes ANY Solidity version to 0.8.28 and redirects all non-JSON output to stderr.

Configure Claude Desktop with:

{
  "mcpServers": {
    "monad-mcp": {
      "command": "node",
      "args": [
        "/path/to/DropFlow/monad-mcp/strict-mcp-plugin.js"
      ]
    }
  }
}

🚀 Fastest Option: Just Deploy a Simple Contract

Skip Claude entirely and deploy a simple storage contract directly:

npm run simple-deploy

This deploys a pre-configured SimpleStorage contract using Solidity 0.8.28.

Example Deployments

The repository includes several examples:

# Deploy the SimpleStorage contract (simplest)
npm run deploy-storage

# Deploy the SimpleToken contract
npm run deploy-token

# Alternative clean deployment script with better error handling
npm run deploy-token-clean

Custom Contract Deployment

To deploy a custom contract:

1. Create your contract file with pragma solidity 0.8.28
2. Use the deployment utility in your script:

const { compileAndDeploy } = require('./src/utils/contract-deployer');
const fs = require('fs');
const { PRIVATE_KEY } = require('./env.js');

const contractSource = fs.readFileSync('path/to/your/contract.sol', 'utf8');

async function deploy() {
  const result = await compileAndDeploy(
    contractSource,
    PRIVATE_KEY,
    [], // constructor args
    { solcVersion: '0.8.28', saveArtifacts: true }
  );

  console.log(`Contract deployed at: ${result.address}`);
}

deploy();

Troubleshooting

If you encounter JSON parsing errors like:

MCP monad-mcp: Unexpected token 'S', "Starting c"... is not valid JSON

Try these solutions in order:

1. Use the ultra-simple MCP plugin: npm run start-simple-mcp (always succeeds with mock data)
2. Use the strict MCP plugin: npm run start-strict-mcp (fixes version issues automatically)
3. Check your contract's pragma version: npm run check-solidity examples/YourContract.sol
4. Use the clean deployment script: npm run deploy-token-clean
5. Fix your contract's Solidity version: npm run fix-solidity YourContract.sol
6. Deploy directly without Claude: npm run simple-deploy

Always check your contract's pragma version first:

pragma solidity 0.8.x;  // Must be exact version ^0.8.0 or similar

Template Contract

A template contract is available at monad-mcp/solidity-template.sol that you can use as a starting point for any new contracts.

Security Note

• Always keep your env.js file secure and never commit it to version control.
• The private key is never hardcoded, printed, or exposed in logs or code.

MonDeployer