RTK Token Optimization

RTK Token Optimization

RTK is a high-performance CLI proxy written in Rust. It intercepts commands like git status, npm install, etc., and rewrites their output to be dramatically more token-efficient.

Meta Commands (always use rtk directly)

rtk gain              # Show token savings analytics
rtk gain --history    # Show command usage history with savings
rtk discover          # Analyze Claude Code history for missed opportunities
rtk proxy <cmd>       # Execute raw command without filtering (for debugging)

Run a specific command with RTK rewriting

rtk <command> [args...]
# Example: rtk git status
# Example: rtk npm test

Installation

# Quick install (Linux/macOS)
curl -fsSL https://raw.githubusercontent.com/rtk-ai/rtk/master/install.sh | sh

# macOS/Linux via Homebrew
brew install rtk-ai/tap/rtk

# Or via cargo (use the explicit Git URL — plain `cargo install rtk`
# may install the wrong package due to a name collision)
cargo install --git https://github.com/rtk-ai/rtk rtk

Installation Verification

rtk --version         # Should show: rtk X.Y.Z
rtk gain              # Should work (not "command not found")
which rtk             # Verify correct binary

⚠️ Name collision: If rtk gain fails, you may have reachingforthejack/rtk (Rust Type Kit) installed instead.

Initialization

This plugin already installs the Claude Code hook — no rtk init needed.

• rtk init --global patches ~/.claude/settings.json with a rtk hook claude PreToolUse entry — the non-plugin alternative to this plugin. Don't combine them: the hook would fire twice (redundant, not harmful).
• rtk init (per-project) installs no hook — it only injects RTK instructions into the project CLAUDE.md and creates a .rtk/filters.toml filter template.

How the Plugin Works

When installed as a Claude Code plugin, RTK's PreToolUse hook intercepts every Bash tool call and rewrites commands through rtk rewrite before execution. This is transparent to Claude — commands run normally but produce compressed, token-efficient output. All rewrite and permission logic lives in the rtk rewrite binary (deny rules pass through to Claude Code's native handling; ask rules rewrite but still prompt the user).

Configuration

Config file: ~/.config/rtk/config.toml (Linux) or ~/Library/Application Support/rtk/config.toml (macOS). View with rtk config, create with rtk config --create.

# Exclude commands from auto-rewriting (prefix, subcommand, or ^regex)
[hooks]
exclude_commands = ["git rebase", "docker exec"]

• RTK_DISABLED=1 <command> — disable RTK for a single invocation
• RTK_HOOK_AUDIT=1 — enable hook audit logging
• Per-project overrides: .rtk/filters.toml in the project root

Requirements

• RTK >= 0.23.0
• jq (for JSON parsing in the hook script)
• If either is missing, the hook warns once on stderr and passes through — safe to install without RTK

Token Savings Examples