README.md•5.72 kB
# Monad MCP Tutorial
This project demonstrates how to create a MCP server that interacts with the Monad testnet. The MCP server provides a tool for checking MON token balances on the Monad testnet.
## What is MCP?
The Model Context Protocol (MCP) is a standard that allows AI models to interact with external tools and services.
In this tutorial, we're creating an MCP server that allows MCP Client (Claude Desktop) to query Monad testnet to check MON balance of an account.
## Prerequisites
- Node.js (v16 or later)
- `npm` or `yarn`
- Claude Desktop
## Getting Started
1. Clone this repository
```shell
git clone https://github.com/bble/monad-mcp.git
```
2. Install dependencies:
```
npm install
```
## Building the MCP server
Monad Testnet related configuration is already added to `index.ts` in the `src` folder.
### Define the server instance
```ts
// Create a new MCP server instance
const server = new McpServer({
name: "monad-testnet",
version: "0.0.1",
// Array of supported tool names that clients can call
capabilities: ["get-mon-balance"]
});
```
### Defining the MON balance tool
```ts
server.tool(
// Tool ID
"get-mon-balance",
// Description of what the tool does
"Get MON balance for an address on Monad testnet",
// Input schema
{
address: z.string().describe("Monad testnet address to check balance for"),
},
// Tool implementation
async ({ address }) => {
try {
// Check MON balance for the input address
const balance = await publicClient.getBalance({
address: address as `0x${string}`,
});
// Return a human friendly message indicating the balance.
return {
content: [
{
type: "text",
text: `Balance for ${address}: ${formatUnits(balance, 18)} MON`,
},
],
};
} catch (error) {
// If the balance check process fails, return a graceful message back to the MCP client indicating a failure.
return {
content: [
{
type: "text",
text: `Failed to retrieve balance for address: ${address}. Error: ${
error instanceof Error ? error.message : String(error)
}`,
},
],
};
}
}
);
```
### Add functionality to query NFT count
```
### Add functionality to query NFT count
server.tool(
// Function identifier
"get-nft-count",
// Function description
"Query the number of NFTs held by an address on the Monad testnet",
// Parameter definition
{
address: z.string().describe("The Monad testnet address to query"),
nftContract: z.string().describe("NFT contract address")
},
// Function implementation
async ({ address, nftContract }) => {
try {
// Call the contract's balanceOf method to get the NFT count
const balance = await publicClient.readContract({
address: nftContract as `0x${string}`,
abi: [
{
inputs: [{ name: "owner", type: "address" }],
name: "balanceOf",
outputs: [{ name: "", type: "uint256" }],
stateMutability: "view",
type: "function"
}
],
functionName: "balanceOf",
args: [address as `0x${string}`]
});
// Return the formatted query result
return {
content: [
{
type: "text",
text: `The address ${address} holds ${balance.toString()} NFTs in contract ${nftContract}.`,
},
],
};
} catch (error) {
// Error handling
return {
content: [
{
type: "text",
text: `Failed to query NFT count for address ${address}: ${
error instanceof Error ? error.message : String(error)
}`,
},
],
};
}
}
);
```
### Initialize the transport and server from the `main` function
```ts
async function main() {
// Create a transport layer using standard input/output
const transport = new StdioServerTransport();
// Connect the server to the transport
await server.connect(transport);
console.error("Monad testnet MCP Server running on stdio");
}
```
### Build the project
```shell
npm run build
```
The server is now ready to use!
### Adding the MCP server to Claude Desktop
1. Open "Claude Desktop"

2. Open Settings
Claude > Settings > Developer

3. Open `claude_desktop_config.json`

4. Add details about the MCP server and save the file.
```json
{
"mcpServers": {
...
"monad-mcp": {
"command": "node",
"args": [
"/<path-to-project>/build/index.js"
]
}
}
}
```
5. Restart "Claude Desktop"
### Using the MCP server
Here's the final result

## Further Resources
- [Model Context Protocol Documentation](https://modelcontextprotocol.io/introduction)
- [Monad Documentation](https://docs.monad.xyz/)
- [Viem Documentation](https://viem.sh/)