RTK (Rust Token Killer): CLI Proxy Cuts LLM Token Consumption 60-90% on Dev Commands

RTK is a single Rust binary that intercepts your terminal commands and compresses the output before it hits the LLM context window. That's it. No configuration philosophy, no agent framework — just less tokens for the same information.

The numbers are immediate: cargo test compresses 155 lines to 3 (98% reduction). git status drops 119 chars to 28 (76% reduction). Overhead is under 10ms. At 12,252 GitHub stars, this is the kind of tool that spreads by saving people money on their first session.

It works transparently with Claude Code, Cursor, Gemini CLI, Codex, Aider, and Windsurf. Install the binary, prefix your commands, and your context window just got dramatically more efficient. The compression is smart — it preserves the semantic content (test results, file statuses, error messages) while stripping the formatting, whitespace, and repetitive structure that LLMs don't need.

The real value isn't just cost savings per token — it's context window efficiency. When your 200K context is half-filled with verbose cargo output, you're paying twice: once in tokens and once in degraded model performance as the useful signal gets buried. RTK addresses both simultaneously. If you're running any agentic coding workflow where tools produce terminal output, this should be in your stack today.