MCP: The bridge connecting large language models and Web3

MCP (Model-Context Protocol) is an open protocol that provides a standardized way for large language models to access external tools, data sources, and services. Unlike traditional plugin systems, MCP adopts a client-server architecture, achieving seamless integration between models and external systems through standardized protocol interfaces.

Core Advantages of MC

• Standardized Interface: Define a unified protocol specification to avoid independent integration solutions for each application development.
• Security: Strict permission control and sandbox mechanisms ensure safe access for external tools.
• Scalability: Supports a variety of tool types, from simple API calls to complex data processing.
• Interoperability: Clients that support MCP can use compatible services to achieve cross-platform compatibility.

Application Scenarios of Web3 and MCP

In the Web3 domain, MCP can provide rich blockchain interaction capabilities for large language models:

• Asset Inquiry: Check token balance, transaction history
• On-chain operations: sending transactions, deploying contracts, calling smart contracts
• DeFi Integration: Interacting with decentralized exchanges, lending protocols, liquidity mining, and other DeFi applications.
• Cross-chain operations: Support for multi-chain asset management and cross-chain transfers.
• NFT Management: Query, Transfer, Trade NFT Assets

This article will build a simple Web3 MCP service using nodejs and typescript, explaining the working principle of MCP and best practices.

Create Project

1. Create a project folder and initialize the project
2. Install the necessary packages
3. Add typescript configuration
4. Modify package.json configuration

Write Server

Create a tool using getBalance of the sepolia testnet as an example:

1. Register an account, activate node services, obtain rpcUrl, and instantiate provider.
2. Write tool logic
3. Start the service and add error handling

Debugging Service

Package the js product and execute modelcontextprotocol/inspector for debugging.

Improve logic and integrate

Improve more features, such as supporting multiple EVM networks, querying gas, sending transactions, querying token information, and other commonly used methods. After packaging, it can be referenced in IDEs that support MCP integration (such as Cursor).

Usage Example

In Cursor's AI assistant, you can interact with the codebase using natural language:

• Check address balance: "Check the balance of this address 0xE21E97Ad8B527acb90F0b148EfaFbA46625382cE on sepolia"
• Transfer operation: "Send 0.1 ETH to this address 0x2c1d9ef7ccede70d77e6038701cd63138dd920a0"

Future Outlook

The combination of Web3 and MCP opens up a new world full of possibilities. Directions that can be explored in the future include:

• Supports more blockchains (such as Bitcoin, Solana, Tron)
• Integrate cross-chain functionality to achieve asset conversion between different chains.
• Deep integration of DeFi protocols
• NFT market operation optimization
• Complex Cross-Chain Asset Management

These features are expected to be achieved through simple conversations, greatly enhancing user experience and operational efficiency.