Substrate Blockchain MCP server

This Substrate MCP server provides a bridge between Substrate blockchains and AI applications through the Model Context Protocol. It allows for dynamic interaction with blockchain data through a standardized interface.

Introduction to Substrate MCP Server

The Substrate MCP Server implements the Model Context Protocol (MCP) for Substrate-based blockchains. It enables dynamic querying of blockchain data, submission of transactions, and access to system information through a standardized interface that can be easily integrated with AI tools and applications.

Installation

Follow these steps to install and set up the Substrate MCP server:

Prerequisites

• Rust programming language
• Access to a Substrate node endpoint (WebSocket)
• A valid signing keypair (as hex)
• Runtime metadata file for your target chain

Building from Source

Clone the repository and build the project:

git clone https://github.com/ThomasMarches/substrate-mcp-rs.git
cd substrate-mcp-rs
cargo build --release

Configuration

Environment Setup

Create a .env file in the project root with the following variables:

# WebSocket endpoint for the Substrate node
RPC_URL=wss://your-node-url.example.com

# Signing keypair as hex (32 bytes)
SIGNING_KEYPAIR_HEX=your_signing_keypair_hex_here

Generating a Signing Keypair

You can generate a keypair using subkey:

subkey generate --scheme Sr25519 --output-type Json

Use the secretSeed field (without the 0x prefix if present) for the SIGNING_KEYPAIR_HEX environment variable.

Runtime Metadata

Before building, you must obtain and place the runtime metadata for your chain:

1. Export the metadata from your node:

subxt metadata -f bytes > artifacts/metadata.scale

2. Ensure the file is named metadata.scale and located in the artifacts/ directory.

Running the Server

Start the MCP server with:

cargo run --release

The server will start and listen for MCP requests via stdio.

Integrating with Cursor

To use this MCP server with Cursor:

1. Build your server in release mode:

cargo build --release

2. In your project (or global) .cursor/mcp.json file, add an entry for your server:

{
  "mcpServers": {
    "substrate-mcp-rs": {
      "command": "$PROJECT_ROOT_ABSOLUTE_PATH/target/release/substrate-mcp-rs",
      "args": []
    }
  }
}

3. Replace the command path with the absolute path to your built binary if needed.

4. Restart Cursor for it to detect and connect to your Substrate MCP server.

Available Tools

The server provides the following tools for interacting with a Substrate blockchain:

• query_balance: Fetch the balance of an account
• list_pallets: List all pallets in the runtime
• list_pallet_entries: List all storage entries for a pallet
• dynamic_runtime_call: Execute a runtime API call
• send_dynamic_signed_transaction: Construct, sign, and send a transaction
• query_storage: Query storage by pallet and entry
• get_latest_events: Get all events from the latest block
• find_events: Find specific events by pallet and variant
• get_latest_block: Get details about the latest block
• get_block_by_hash: Get block details by hash
• find_extrinsics: Find extrinsics in the latest block
• get_system_info: Get system info via RPC
• custom_rpc: Make a custom RPC call

Use Cases

AI-Driven Blockchain Operations

• Integrate with LLMs to process natural language queries about blockchain data
• Build chatbots that can fetch balances or explain on-chain activity
• Provide live updates on blockchain activity to development tools

Custom Dashboards and Monitoring

• Create dashboards displaying real-time blockchain data
• Set up alerts for critical events
• Use AI agents to analyze events and detect suspicious activity

How to install this MCP server

For Claude Code

To add this MCP server to Claude Code, run this command in your terminal:

claude mcp add-json "substrate-mcp-rs" '{"command":"$PROJECT_ROOT_ABSOLUTE_PATH/target/release/substrate-mcp-rs","args":[]}'

See the official Claude Code MCP documentation for more details.

For Cursor

There are two ways to add an MCP server to Cursor. The most common way is to add the server globally in the ~/.cursor/mcp.json file so that it is available in all of your projects.

If you only need the server in a single project, you can add it to the project instead by creating or adding it to the .cursor/mcp.json file.

Adding an MCP server to Cursor globally

To add a global MCP server go to Cursor Settings > Tools & Integrations and click "New MCP Server".

When you click that button the ~/.cursor/mcp.json file will be opened and you can add your server like this:

{
    "mcpServers": {
        "substrate-mcp-rs": {
            "command": "$PROJECT_ROOT_ABSOLUTE_PATH/target/release/substrate-mcp-rs",
            "args": []
        }
    }
}

Adding an MCP server to a project

To add an MCP server to a project you can create a new .cursor/mcp.json file or add it to the existing one. This will look exactly the same as the global MCP server example above.

How to use the MCP server

Once the server is installed, you might need to head back to Settings > MCP and click the refresh button.

The Cursor agent will then be able to see the available tools the added MCP server has available and will call them when it needs to.

You can also explicitly ask the agent to use the tool by mentioning the tool name and describing what the function does.

For Claude Desktop

To add this MCP server to Claude Desktop:

1. Find your configuration file:

• macOS: ~/Library/Application Support/Claude/claude_desktop_config.json
• Windows: %APPDATA%\Claude\claude_desktop_config.json
• Linux: ~/.config/Claude/claude_desktop_config.json

2. Add this to your configuration file:

{
    "mcpServers": {
        "substrate-mcp-rs": {
            "command": "$PROJECT_ROOT_ABSOLUTE_PATH/target/release/substrate-mcp-rs",
            "args": []
        }
    }
}

3. Restart Claude Desktop for the changes to take effect