A Model Context Protocol (MCP) server that provides onchain tools for Claude AI, allowing it to interact with the Base blockchain and Coinbase API
npm install base-mcp

A Model Context Protocol (MCP) server that provides onchain tools for AI applications like Claude Desktop and Cursor, allowing them to interact with the Base Network and Coinbase API.
This MCP server extends any MCP client's capabilities by providing tools to do anything on Base:
- Retrieve wallet addresses
- List wallet balances
- Transfer funds between wallets
- Deploy smart contracts
- Interact with Morpho vaults for onchain lending
- Call contract functions
- Onramp funds via Coinbase
- Manage ERC20 tokens
- List and transfer NFTs (ERC721 and ERC1155)
- Buy OpenRouter credits with USDC
- Resolve Farcaster usernames to Ethereum addresses
The server interacts with Base, powered by Base Developer Tools and AgentKit.
Base MCP is designed to be extensible, allowing you to add your own third-party protocols, tools, and data sources. This section provides an overview of how to extend the Base MCP server with new capabilities.
If you want to add a new tool to the Base MCP server, follow these steps:
1. Create a new directory in the src/tools directory for your tool
2. Implement the tool following the existing patterns:
- index.ts: Define and export your tools. Tools are defined as AgentKit ActionProviders.
- schemas.ts: Define input schemas for your tools
- types.ts: Define types required for your tools
- utils.ts: Utilities for your tools
3. Add your tool to the list of available tools in src/main.ts
4. Add documentation for your tool in the README.md
5. Add examples of how to use your tool in examples.md
6. Write tests for your tool
The Base MCP server follows this structure for tools:
```
src/
āāā tools/
ā āāā [TOOL_NAME]/ <-------------------------- ADD DIR HERE
ā ā āāā index.ts (defines and exports tools)
ā ā āāā schemas.ts (defines input schema)
ā āāā utils/ (shared tool utilities)
When developing new tools for Base MCP:
- Follow the existing code style and patterns
- Ensure your tool has a clear, focused purpose
- Provide comprehensive input validation
- Include detailed error handling
- Write thorough documentation
- Add examples demonstrating how to use your tool
- Include tests for your tool
For more detailed information on contributing to Base MCP, including adding new tools and protocols, see the CONTRIBUTING.md file.
- Node.js (v16 or higher)
- npm or yarn
- Coinbase API credentials (API Key Name and Private Key)
- A wallet seed phrase
- Coinbase Project ID (for onramp functionality)
- Alchemy API Key (required for NFT functionality)
- Optional: OpenRouter API Key (for buying OpenRouter credits)
`bashInstall globally
npm install -g base-mcp
Once the package is installed, you can configure clients with the following command:
`bash
base-mcp --init
`$3
1. Clone this repository:
`bash
git clone https://github.com/base/base-mcp.git
cd base-mcp
`2. Install dependencies:
`bash
npm install
`3. Build the project:
`bash
npm run build
`4. Optionally, link it globally:
`bash
npm link
`Configuration
Create a
.env file with your credentials:`
Coinbase API credentials
You can obtain these from the Coinbase Developer Portal: https://cdp.coinbase.com/
COINBASE_API_KEY_NAME=your_api_key_name
COINBASE_API_PRIVATE_KEY=your_private_keyWallet seed phrase (12 or 24 words)
This is the mnemonic phrase for your wallet
SEED_PHRASE=your seed phrase hereCoinbase Project ID (for onramp functionality)
You can obtain this from the Coinbase Developer Portal
COINBASE_PROJECT_ID=your_project_idAlchemy API Key (required for NFT functionality)
You can obtain this from https://alchemy.com
ALCHEMY_API_KEY=your_alchemy_api_keyOpenRouter API Key (optional for buying OpenRouter credits)
You can obtain this from https://openrouter.ai/keys
OPENROUTER_API_KEY=your_openrouter_api_keyChain ID (optional for Base Sepolia testnet)
Use 84532 for Base Sepolia testnet
You do not have to include this if you want to use Base Mainnet
CHAIN_ID=your_chain_idNeynar API Key (required for Farcaster functionality)
You can obtain this from https://neynar.com
NEYNAR_API_KEY=your_neynar_api_key
`Testing
Test the MCP server to verify it's working correctly:
`bash
npm test
`This script will verify that your MCP server is working correctly by testing the connection and available tools.
Examples
See the examples.md file for detailed examples of how to interact with the Base MCP tools through Claude.
Integration with Claude Desktop
To add this MCP server to Claude Desktop:
1. Create or edit the Claude Desktop configuration file at:
- macOS:
~/Library/Application Support/Claude/claude_desktop_config.json
- Windows: %APPDATA%\Claude\claude_desktop_config.json
- Linux: ~/.config/Claude/claude_desktop_config.jsonYou can easily access this file via the Claude Desktop app by navigating to Claude > Settings > Developer > Edit Config.
2. Add the following configuration:
`json
{
"mcpServers": {
"base-mcp": {
"command": "npx",
"args": ["-y", "base-mcp@latest"],
"env": {
"COINBASE_API_KEY_NAME": "your_api_key_name",
"COINBASE_API_PRIVATE_KEY": "your_private_key",
"SEED_PHRASE": "your seed phrase here",
"COINBASE_PROJECT_ID": "your_project_id",
"ALCHEMY_API_KEY": "your_alchemy_api_key",
"PINATA_JWT": "your_pinata_jwt",
"OPENROUTER_API_KEY": "your_openrouter_api_key",
"CHAIN_ID": "optional_for_base_sepolia_testnet"
},
"disabled": false,
"autoApprove": []
}
}
}
`3. Restart Claude Desktop for the changes to take effect.
Available Tools
$3
Retrieves the address for your wallet.
Example query to Claude:
> "What's my wallet address?"
$3
Lists all balances for your wallet.
Example query to Claude:
> "Show me my wallet balances."
$3
Transfers funds from your wallet to another address.
Parameters:
-
destination: The address to which to transfer funds
- assetId: The asset ID to transfer
- amount: The amount of funds to transferExample query to Claude:
> "Transfer 0.01 ETH to 0x1234567890abcdef1234567890abcdef12345678."
$3
Deploys a smart contract to the blockchain.
Parameters:
-
constructorArgs: The arguments for the contract constructor
- contractName: The name of the contract to deploy
- solidityInputJson: The JSON input for the Solidity compiler containing contract source and settings
- solidityVersion: The version of the solidity compilerExample query to Claude:
> "Deploy a simple ERC20 token contract for me."
$3
Checks the reputation of an address.
Parameters:
-
address: The Ethereum address to checkExample query to Claude:
> "What's the reputation of 0x1234567890abcdef1234567890abcdef12345678?"
$3
Gets the vaults for a given asset on Morpho.
Parameters:
-
assetSymbol: Asset symbol by which to filter vaults (optional)Example query to Claude:
> "Show me the available Morpho vaults for USDC."
$3
Calls a contract function on the blockchain.
Parameters:
-
contractAddress: The address of the contract to call
- functionName: The name of the function to call
- functionArgs: The arguments to pass to the function
- abi: The ABI of the contract
- value: The value of ETH to send with the transaction (optional)Example query to Claude:
> "Call the balanceOf function on the contract at 0x1234567890abcdef1234567890abcdef12345678."
$3
Gets the assets available for onramping in a given country/subdivision.
Parameters:
-
country: ISO 3166-1 two-digit country code string representing the purchasing user's country of residence
- subdivision: ISO 3166-2 two-digit country subdivision code (required for US)Example query to Claude:
> "What assets can I onramp in the US, specifically in New York?"
$3
Gets a URL for onramping funds via Coinbase.
Parameters:
-
amountUsd: The amount of funds to onramp
- assetId: The asset ID to onrampExample query to Claude:
> "I want to onramp $100 worth of ETH."
$3
Gets the balance of an ERC20 token.
Parameters:
-
contractAddress: The address of the ERC20 contractExample query to Claude:
> "What's my balance of the token at 0x1234567890abcdef1234567890abcdef12345678?"
$3
Transfers an ERC20 token to another address.
Parameters:
-
contractAddress: The address of the ERC20 contract
- toAddress: The address of the recipient
- amount: The amount of tokens to transferExample query to Claude:
> "Transfer 10 USDC to 0x1234567890abcdef1234567890abcdef12345678."
$3
Lists NFTs owned by a specific address.
Parameters:
-
ownerAddress: The address of the owner whose NFTs to list
- limit: Maximum number of NFTs to return (default: 50)Example query to Claude:
> "Show me the NFTs owned by 0x89A93a48C6Ef8085B9d07e46AaA96DFDeC717040."
$3
Transfers an NFT to another address. Supports both ERC721 and ERC1155 standards.
Parameters:
-
contractAddress: The address of the NFT contract
- tokenId: The token ID of the NFT to transfer
- toAddress: The address of the recipient
- amount: The amount to transfer (only used for ERC1155, default: 1)Example query to Claude:
> "Transfer my NFT with contract 0x3F06FcF75f45F1bb61D56D68fA7b3F32763AA15c and token ID 56090175025510453004781233574040052668718235229192064098345825090519343038548 to 0x1234567890abcdef1234567890abcdef12345678."
$3
Buys OpenRouter credits with USDC.
Parameters:
-
amountUsd: The amount of credits to buy, in USDExample query to Claude:
> "Buy $20 worth of OpenRouter credits."
Security Considerations
- The configuration file contains sensitive information (API keys and seed phrases). Ensure it's properly secured and not shared.
- Consider using environment variables or a secure credential manager instead of hardcoding sensitive information.
- Be cautious when transferring funds or deploying contracts, as these operations are irreversible on the blockchain.
- When using the onramp functionality, ensure you're on a secure connection.
- Verify all transaction details before confirming, especially when transferring funds or buying credits.
Troubleshooting
If you encounter issues:
1. Check that your Coinbase API credentials are correct
2. Verify that your seed phrase is valid
3. Ensure you're on the correct network (Base Mainnet)
4. Check the Claude Desktop logs for any error messages
License
Contributing
Contributions are welcome! Please feel free to submit a Pull Request.
For detailed guidelines on contributing to Base MCP, including:
- Reporting bugs
- Suggesting enhancements
- Development setup
- Coding standards
- Adding new tools, protocols, and data sources (see also the Extending Base MCP section above)
- Testing requirements
- Documentation standards
Please refer to our comprehensive CONTRIBUTING.md guide.
Basic contribution steps:
1. Fork the repository
2. Create your feature branch (
git checkout -b feature/amazing-feature)
3. Commit your changes (git commit -m 'Add some amazing feature')
4. Push to the branch (git push origin feature/amazing-feature`)Please make sure your code follows the existing style and includes appropriate tests.