GitHub - rtk-ai/rtk: CLI proxy that reduces LLM token consumption by 60-90% on common dev commands. Single Rust binary, zero dependencies

rtk (Rust Token Killer) is a CLI proxy tool that intercepts and compresses command outputs before they reach an LLM context window, reducing token consumption by 60-90%. It works as a transparent proxy for common dev commands like git, cargo, pytest, docker, and more. The recommended setup uses a Claude Code PreToolUse hook that automatically rewrites commands (e.g., `git status` → `rtk git status`) without requiring manual intervention. Key features include smart filtering, grouping, deduplication, truncation, a tee feature for full output recovery on failures, token savings analytics via `rtk gain`, and a `rtk discover` command to identify missed savings opportunities. Typical 30-minute Claude Code sessions drop from ~150K tokens to ~45K tokens.