ThomasMarches/substrate-mcp-rs

A Model Context Protocol (MCP) server for Substrate blockchains, written in Rust. This project exposes dynamic Substrate blockchain operations (querying balances, blocks, pallets, storage, events, and more) via the MCP protocol, and is fully configurable via environment variables.
Designed to interface with the subxt crate.
✨ Features
- Query account balances and storage dynamically
- List pallets and their entries
- Fetch and filter events and extrinsics
- Submit and watch dynamic signed transactions
- Access system and block information
- Custom RPC calls to Substrate nodes
🚀 Potential Use Cases
1. AI-Driven Blockchain Operations
- Integrate with LLMs (like Cursor or Claude) to allow users to ask questions in natural language (e.g., "What was the last transfer from Alice?"), which are translated into MCP tool calls.
- Build a chatbot that can answer questions, fetch balances, or explain on-chain activity using your MCP server as the backend.
- Use the MCP server to provide live updates on-chain activity, such as balance changes or transaction statuses, to development tools like VSCode, Cursor, Claude Code, etc.
2. Custom Dashboards and Monitoring
- Create custom dashboards and monitoring systems for your Substrate blockchain
- Display real-time data and analytics on your blockchain operations
- Set up alerts and notifications for critical events
- Use AI agents to detect suspicious activity by analyzing events and extrinsics in real time.
🛠️ Requirements
- Rust
- Access to a Substrate node endpoint (WebSocket)
- A valid signing keypair (as hex)
- Runtime metadata file for your target chain (see below for naming and placement)
📦 Installation
Clone the repository and build:
⚙️ Configuration
Create a .env file in the project root with the following variables:
Generating a Signing Keypair
You can generate a keypair and get the secret seed in hex using subkey:
Use the secretSeed field (strip the 0x prefix if present) for SIGNING_KEYPAIR_HEX.
Obtaining and Placing Runtime Metadata
Export the runtime metadata from your node and place it at artifacts/metadata.scale:
**Important:** The file must be named metadata.scale and located in the artifacts/ directory before building. The build will fail if this file is missing or misnamed.
▶️ Usage
To start the MCP server:
The server will start and listen for MCP requests via stdio.
🖇️ Integrating with Cursor
To use this MCP server with Cursor, you need to add it to your Cursor MCP configuration. This allows Cursor to discover and interact with your Substrate MCP server.
1. Build your server in release mode:
2. Locate the path to the built binary (typically target/release/substrate-mcp-rs).
3. In your project (or global) .cursor/mcp.json file, add an entry for your server. For example:
- Replace the command path with the absolute path to your built binary if it differs.
4. Restart Cursor. It should now detect and connect to your Substrate MCP server, making its tools available for use.