rust-analyzer

This MCP server provides an integration layer for rust-analyzer, exposing a set of MCP-compatible tools that let you analyze Rust code, navigate symbols, and perform common IDE-like actions via AI assistants. Once running, you can query the server for symbol extraction, definitions, references, hover information, completions, formatting, code actions, diagnostics, and workspace-wide diagnostics. The server speaks the MCP protocol over stdio and is designed to work with Claude Code and other MCP clients by referencing the rust-analyzer-mcp binary in your PATH or by providing a direct path when built from source.

To use it, configure the MCP client to point at the rust-analyzer-mcp command. If you installed from crates.io, the command will typically be rust-analyzer-mcp in your PATH; if you built from source, use the full path to the binary (e.g., target/release/rust-analyzer-mcp or ~/.cargo/bin/rust-analyzer-mcp). Once connected, you can leverage the available tools under the rust_analyzer_* namespace (e.g., rust_analyzer_definition, rust_analyzer_hover, rust_analyzer_completion) to perform code analysis, navigation, and editing tasks directly from your prompts or UI.

Prerequisites:\n- Rust toolchain (rustc, cargo) and a compatible Rust environment.\n- rust-analyzer installed and available in PATH if you plan to use the executable wrapper.\n- Optional: a Rust project workspace for best results.\n\nStep 1: Install the MCP server binary\n- Option A: Install from crates.io (recommended)\n - cargo install rust-analyzer-mcp\n - This places rust-analyzer-mcp in your Cargo bin directory (usually ~/.cargo/bin).\n\n- Option B: Build from source\n - git clone https://github.com/zeenix/rust-analyzer-mcp.git\n - cd rust-analyzer-mcp\n - cargo build --release\n - The binary will be at target/release/rust-analyzer-mcp. You can also run cargo run during development.\n\nStep 2: Verify installation\n- Ensure the binary runs: rust-analyzer-mcp --version (or simply run the binary to see help output).\n- If you built from source, you can run: ./target/release/rust-analyzer-mcp.\n\nStep 3: Run in development or production mode\n- Development: cargo run (in the project root) or cargo run --release for optimized builds.\n- Production: Use the installed binary in your PATH (rust-analyzer-mcp).\n\nStep 4: Connect your MCP client\n- Point your MCP client to the rust-analyzer-mcp command. If you installed from crates.io, this should be available in PATH. If you built from source, provide the full path to the binary.

Tips and common issues:\n- Rust toolchain: Make sure you have Rust 1.70 or newer and Cargo installed.\n- rust-analyzer availability: Ensure rust-analyzer is installed and accessible in PATH if you rely on external tooling. You can install it via rustup component add rust-analyzer or cargo install rust-analyzer.\n- Workspace considerations: The server works best with a valid Cargo.toml workspace. Point the MCP client to the workspace root when analyzing a project.\n- Logging: For verbose output, run with RUST_LOG=debug to diagnose lint or analysis issues.\n- CLI configuration: If you’re embedding in Claude Code or Claude Desktop, you can configure the command in .mcp.json or the corresponding UI settings to point to rust-analyzer-mcp.\n- Updates: When upgrading, revalidate that the new binary path (or updated PATH) is reflected in your MCP client configuration.\n- Performance: Build in release mode for production deployments to reduce overhead.