Substrate MCP Server

What is Substrate MCP Server?

An MCP server for Substrate blockchains, written in Rust. It exposes dynamic blockchain operations—querying balances, blocks, pallets, storage, events, and more—via the Model Context Protocol. Designed for developers integrating Substrate data into LLM‑driven tools, dashboards, or monitoring systems.

How to use Substrate MCP Server?

Clone the repository, place a runtime metadata file at artifacts/metadata.scale, create a .env file with RPC_URL and SIGNING_KEYPAIR_HEX variables, then build with cargo build --release and run with cargo run --release. The server communicates via stdio. Integrate with Cursor by adding the binary path to .cursor/mcp.json.

Key features of Substrate MCP Server

• Query account balances and storage dynamically
• List pallets and their storage entries
• Fetch and filter events and extrinsics
• Submit and watch dynamic signed transactions
• Access system and block information
• Make custom RPC calls to Substrate nodes

Use cases of Substrate MCP Server

• AI‑driven blockchain operations via natural language queries (e.g., “What was the last transfer from Alice?”)
• Real‑time on‑chain monitoring in development tools like VSCode, Cursor, or Claude Code
• Custom dashboards and alerts for Substrate blockchains
• AI‑agent detection of suspicious activity by analyzing events and extrinsics

FAQ from Substrate MCP Server

What are the requirements to run Substrate MCP Server?

Rust, access to a Substrate node WebSocket endpoint, a valid signing keypair as hex, and a runtime metadata file (artifacts/metadata.scale).

How do I generate a signing keypair?

Use subkey generate --scheme Sr25519 --output-type Json. Use the secretSeed field (strip the 0x prefix if present) for the SIGNING_KEYPAIR_HEX environment variable.

How do I obtain and place the runtime metadata?

Run subxt metadata -f bytes > artifacts/metadata.scale from your project root. The file must be named metadata.scale and placed in the artifacts/ directory before building.

How do I integrate this server with Cursor?

After building, add an entry to your project’s .cursor/mcp.json with the command set to the absolute path of the built binary (e.g., target/release/substrate-mcp-rs). Restart Cursor to detect the server.

What tools does the server expose?

It provides 14 tools including query_balance, list_pallets, send_dynamic_signed_transaction, get_latest_events, find_extrinsics, custom_rpc, and more.