setup

name	setup
description	Bootstrap the Rust dev environment — verify rustup, toolchain, rust-analyzer, cargo tools, env vars.

/setup

Bootstrap (or re-verify) the development environment. Idempotent — safe to re-run.

Steps

1. Verify rustup is installed

rustup --version

If missing: stop and tell the user to install rustup from https://rustup.rs/. Do not attempt to install it without asking.

2. Verify the active toolchain

rustup show active-toolchain

If a rust-toolchain.toml file exists in the project root, verify the pinned toolchain is installed:

rustup toolchain list

If the pinned toolchain is missing, install it:

rustup toolchain install "$(grep 'channel' rust-toolchain.toml | cut -d'"' -f2)"

3. Verify rust-analyzer is available

rustup component list --installed | grep rust-analyzer

If not installed, add it:

rustup component add rust-analyzer

Also check that the binary is reachable:

rust-analyzer --version

If rust-analyzer is not found even after rustup component add, warn the user — it may need to be installed as a standalone binary or via their editor's extension.

4. Verify required cargo components

Check for and install if missing:

# rustfmt
rustup component list --installed | grep rustfmt || rustup component add rustfmt

# clippy
rustup component list --installed | grep clippy || rustup component add clippy

# llvm-cov (coverage)
cargo llvm-cov --version 2>/dev/null || cargo install cargo-llvm-cov
rustup component list --installed | grep llvm-tools || rustup component add llvm-tools-preview

5. Verify rust-analyzer-mcp is installed

rust-analyzer-mcp is the MCP server that exposes rust-analyzer to Claude Code. Check for it:

rust-analyzer-mcp --version 2>/dev/null || cargo install rust-analyzer-mcp

Then verify .mcp.json exists at the project root and contains the server entry. Read the file if it exists:

cat .mcp.json 2>/dev/null

If .mcp.json is missing or does not contain a rust-analyzer entry under mcpServers, create or merge it:

{
  "mcpServers": {
    "rust-analyzer": {
      "command": "rust-analyzer-mcp"
    }
  }
}

If .mcp.json already exists with other servers, add the rust-analyzer entry alongside them — do not overwrite the whole file. Use jq if available:

jq '.mcpServers["rust-analyzer"] = {"command": "rust-analyzer-mcp"}' .mcp.json > .mcp.json.tmp \
  && mv .mcp.json.tmp .mcp.json

Note: .mcp.json should be committed to the repo so every contributor and CI run picks up the same MCP servers automatically.

6. Run cargo check

cargo check

This verifies the project compiles without producing build artefacts. If it fails, report the compiler error verbatim — do not attempt to fix compilation errors during setup.

7. Ensure .env exists (if .env-template is present)

test -f .env || (test -f .env-template && cp .env-template .env)

If .env was just created, enumerate the keys the user needs to fill in (read .env-template).

8. Report

Print a short status block:

Setup status
  rustup              : <version>
  toolchain           : <active toolchain>
  rust-analyzer       : <version | missing>
  rustfmt             : <installed | missing>
  clippy              : <installed | missing>
  cargo-llvm-cov      : <version | missing>
  rust-analyzer-mcp   : <version | missing>
  .mcp.json           : <present | created | missing rust-analyzer entry>
  cargo check         : <ok | FAILED>
  .env                : <present | created from template | not applicable>
  RUST_LOG            : <set | unset>

Keep it tight — one line per item. If everything is green, end with "Ready." If anything is yellow/red, list the next action explicitly.