Rust

rust-mcp

A Model Context Protocol (MCP) server for Rust development. It gives AI assistants (e.g. Cursor, Claude Code) compiler-accurate tools—Cargo commands, rust-analyzer semantics, refactors, Mermaid diagrams, sandbox execution—with token-efficient output and path safety.

Use it as your daily Rust MCP server, or fork it as a template to build your own MCP server. See Creating your own MCP server.

Features

• Cargo: cargo_workspace_action — check, clippy, test, build (with optional TOON output; build requires approval).
• Semantics: analyze_codebase_symbol — hover, references, definition, type, traits, borrow_graph, doc (rust-analyzer-backed).
• Structure: inspect_codebase_structure — diagnostics, items, snapshot, diff (with detail: "summary" or "full").
• Diagrams: generate_mermaid_diagram — crate graph, file structure, trait hierarchy.
• Refactor: refactor — rename symbol (with optional apply + cargo check); extract/change-signature stubs.
• Security: security_ops — validate MCP config, scan invisible Unicode, TOON encode.
• Sandbox: sandbox_run — run scripts with timeout and output caps (approval required).
• Cursor: cursor_init_rules — seed .cursor/rules/ for Rust projects.
• State DB (optional): manage_shared_memory, find_crate_usages; knowledge feature: search_docs (RAG).

Resources: skills via skill://<name>. Path guard blocks .env, .ssh, and other sensitive paths.

Requirements

• Rust 1.70+ (rustup)
• Cursor (or any MCP client) using stdio transport

Install & run

git clone https://github.com/YOUR_ORG/rust-mcp.git   # replace YOUR_ORG with the repo owner
cd rust-mcp
cargo build --release

Binary: target/release/rust-mcp.

Cursor (this repo): Open this folder in Cursor. The project .cursor/mcp.json starts the server (e.g. cargo run --release or the binary). Restart Cursor after changing config.

Cursor (another project): Add to that project’s .cursor/mcp.json (or ~/.cursor/mcp.json):

{
  "mcpServers": {
    "rust-mcp": {
      "command": "/path/to/rust-mcp/target/release/rust-mcp",
      "args": ["--client=cursor"]
    }
  }
}

Use the absolute path to the binary. --client=cursor skips server-side confirmation prompts and lets Cursor handle approvals.

CLI & env

Subcommands (no server):

• rust-mcp index-workspaces <path>... — index workspaces for find_crate_usages.
• rust-mcp index-docs <path>... — index docs for search_docs (requires --features knowledge, Ollama with embedding model).

Optional features

cargo build --release --features "wasm"           # sandbox_run: run WASI .wasm
cargo build --release --features "knowledge"       # search_docs (LanceDB + Ollama)

See FEATURES.md for the full list (some tool names there reflect an older API; the server uses consolidated tools as in this README).

Documentation

• SETUP.md — Build, Cursor config, troubleshooting.
• FEATURES.md — Capabilities and options.
• documentation/ — Proposals, architecture, HITL, sandbox, creating your own server.
• documentation/PUBLISHING-CHECKLIST.md — Pre-publish steps before going public.

License

Dual-licensed under MIT and Apache-2.0; you may use either. See LICENSE-MIT and LICENSE-APACHE.

Contributing

See CONTRIBUTING.md.