cratedex

MCP (Model Context Protocol) server for Rust documentation indexing, full-text search, and project diagnostics.

Quick Start

1. Install:

cargo install cratedex

To upgrade later:

cratedex update

2. Run as a background service (Linux user service):

cratedex install-service --linger

3. Connect your AI coding tool:

# Claude Code
claude mcp add --scope user --transport http cratedex http://127.0.0.1:3737/mcp

# Codex
codex mcp add cratedex --url http://127.0.0.1:3737/mcp

For OpenCode, add an HTTP MCP server entry that points to:

http://127.0.0.1:3737/mcp

Features

• Full-text search across Rust crate documentation (SQLite FTS5)
• Cargo metadata and workspace-aware dependency resolution
• Build diagnostics, outdated dependencies, and security advisories
• Per-project registration with background indexing
• Dual transport: stdio (per-client) or HTTP (shared daemon)

Prerequisites

• Rust toolchain (1.93+)
• Nightly Rust (for rustdoc JSON generation)

Installation

cargo install cratedex

Configuration

Configuration is loaded from (in priority order):

1. Environment variables (CRATEDEX__<SECTION>__<KEY>)
2. ~/.cratedex/cratedex.toml
3. cratedex.toml in the current directory
4. Built-in defaults

See cratedex.toml.example for all options. Key environment variables:

HTTP Security Model

• By default, cratedex only allows loopback binds (127.0.0.1 / localhost).
• Binding to non-loopback interfaces requires explicit opt-in via CRATEDEX__SERVER__ALLOW_REMOTE=true (or install-service --allow-remote).
• If you expose the service beyond localhost, place it behind a reverse proxy that enforces TLS and authentication.
• For additional local protection (multi-user hosts), set CRATEDEX__SERVER__AUTH_TOKEN and send Authorization: Bearer <token>.

MCP Tools

MCP Resources

Deployment Models

stdio -- per-client process

Each MCP client spawns its own cratedex process. Simple to configure, but concurrent clients may contend on the shared database file. Best for single-client setups.

HTTP -- shared daemon

A single cratedex process serves all clients over HTTP. Avoids database lock contention and shares the documentation index across all sessions. Recommended for multi-client environments.

Endpoint: http://<host>:<port>/mcp (default http://127.0.0.1:3737/mcp)

Client Configuration

Claude Code

claude mcp add --scope user --transport http cratedex http://127.0.0.1:3737/mcp

Codex

codex mcp add cratedex --url http://127.0.0.1:3737/mcp

stdio (any MCP client)

Configure the client to spawn the server directly:

{
  "command": "cratedex",
  "args": ["server"],
  "env": {
    "CRATEDEX__SERVER__TRANSPORT": "stdio"
  }
}

Advanced Service Management

Linux: systemd User Service

For a persistent shared HTTP daemon, install cratedex as a systemd user service:

cratedex install-service

This writes a service unit to ~/.config/systemd/user/cratedex.service, runs daemon-reload, and enables + starts the service. The command is idempotent.

To verify:

systemctl --user status cratedex
journalctl --user -u cratedex -f

To remove:

cratedex remove-service

To update the service binary:

cratedex update

For system-level services:

sudo cratedex update --system

Linux: systemd System Service

A system-level service runs a shared daemon under /etc/systemd/system, managed with plain systemctl.

sudo cratedex install-service --system

To verify:

systemctl status cratedex
journalctl -u cratedex -f

To remove:

sudo cratedex remove-service --system

macOS: launchd

cratedex install-service installs a LaunchAgent in ~/Library/LaunchAgents/. Use --system (with sudo) for /Library/LaunchDaemons/.

Windows: Task Scheduler

cratedex install-service installs a user-level scheduled task at logon. System-level Windows Services are not implemented directly; use NSSM for that deployment model.

License

Licensed under either of

• Apache License, Version 2.0 (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
• MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)

at your option.

Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.