rtk-ai/rtk ? reverse-engineered prompt

Build me a command-line tool that helps me save money on LLM API calls. When I'm working with a coding agent, running commands like ls -R, git status, or npm test produces a ton of output that eats up my context window and costs a lot in tokens.

I want a fast, high-performance CLI proxy written in Rust that can be installed as a single binary with no dependencies. It should intercept common developer commands and return a much shorter, filtered, and smarter summary that's optimized for an LLM.

It needs to handle a wide range of commands: file system tools (ls, cat, grep), version control with git, and various test runners like pytest or cargo test. For tests and linters, it should just show the errors and failures. It should be able to hook into my shell so that when I type a regular command, it's automatically proxied to be LLM-friendly. The main goal is to cut my token usage by 80-90% on everyday dev tasks.