rtk
Filters and compresses CLI output by up to 90% before sending context to AI coding agents.
A high-performance Rust CLI proxy that filters bash noise for Claude Code, Cursor, Gemini, and other agents.
rtk is a single Rust binary CLI proxy that intercepts bash tool calls made by AI coding agents. It filters out boilerplate, whitespace, and irrelevant output from over 100 dev commands before sending the text to your LLM context window. You should use it if you rely on terminal-heavy AI agents and want to lower prompt token consumption.
What it is
rtk hooks directly into your AI coding agent to rewrite shell commands into filtered rtk variants before execution. It uses smart filtering, error aggregation, output truncation, and log deduplication across git, test runners, linters, AWS CLI, and package managers. Built-in native agent tools like Claude Code's Read or Grep bypass the bash hook, requiring direct rtk command invocation for those workflows.
Who it's for
It suits developers and engineering teams using CLI-driven AI coding agents like Claude Code, Cursor, Roo Code, or Gemini CLI. It does not suit developers who interact with AI solely through web interfaces or chat GUIs without local terminal execution. It also offers limited impact if your agent context is dominated by file reads rather than command outputs.
Key features
Automatic Shell Hook Integration
Rewrites bash commands like git status to rtk git status automatically prior to agent execution.
Smart Output Filtering
Strips code comments, boilerplate text, and redundant whitespace from command outputs.
Error and Log Aggregation
Groups linter and build errors by rule or file while deduplicating repeated log messages.
Test Runner Compaction
Filters test output across Pytest, Cargo, Vitest, Go, and Jest to return only failures.
Zero-Dependency Rust Binary
Installs via Homebrew, winget, Cargo, or direct binary download as a standalone executable.
Up and running in 3 steps
Our honest verdict
What's great
- Reduces bash output token volume by 60-90% on supported commands.
- Preserves LLM prompt caching by filtering command outputs prior to context insertion.
- Supports over 100 commands across Git, linters, package managers, and AWS CLI.
- Single Rust binary with no runtime dependencies or background daemons.
Where it falls short
- Does not automatically intercept agent-native non-bash tools like Claude Code's built-in Read or Grep.
- Requires manual invocation of rtk subcommands for workflows that bypass the terminal hook system.
- Name collision on crates.io requires installing from Git repository when using Cargo.
- Does not reduce API costs if your LLM usage is dominated by system prompts and non-CLI context.
Pricing & license
rtk is free and open source under the Apache-2.0 license. There are no paid tiers or hosted SaaS offerings mentioned in the project. The only cost is running the binary on your local machine.
Open remote AI-training roles
880 open remote AI-training roles, updated November 15, 2026; most pay $20–$175 an hour. Zekai lists them free; the application goes to the employer’s platform.
Alternatives
Use it, or have us set it up
FAQ
Does rtk break prompt caching in Claude Code?
No. rtk filters command output once before execution, allowing subsequent API calls to cache the reduced context history normally.
Why are my Claude Code Read or Grep tools not auto-filtered?
Claude Code uses native tools for file reading that do not pass through the bash hook system. You must invoke shell commands like rtk read or rg directly.
What causes Cargo installation to fail?
An unrelated project named rtk exists on crates.io. You must install using cargo install --git https://github.com/rtk-ai/rtk.
