cli output compression for token savings with rtk

RTK (Rust Token Kit) - CLI proxy that reduces LLM token consumption by 60-90% on common dev commands. Use rtk to wrap commands like git, ls, cat, grep, test runners, linters, docker, kubectl, and more. Single Rust binary, zero dependencies, minimal overhead. Always prefer rtk wrappers when available for shell commands that produce verbose output.

RTK - Token-Optimized Command Wrapper

RTK filters and compresses command outputs before they reach context. Use it to reduce token consumption by 60-90% on common dev operations.

Quick Reference

Core principle: Prefix supported commands with rtk for compressed output.

Most Common Usage

bash

# Git operations (80-92% savings)
rtk git status
rtk git diff
rtk git log -n 10
rtk git add .
rtk git commit -m "msg"
rtk git push

# File operations
rtk ls .           # Token-optimized tree
rtk read file.rs   # Smart file reading
rtk grep "pattern" .

# Testing (90% savings on failures)
rtk test cargo test
rtk test npm test
rtk vitest run
rtk playwright test
rtk pytest
rtk go test

# Linting (80-85% savings)
rtk lint           # ESLint grouped by rule
rtk tsc            # TypeScript errors by file
rtk cargo clippy
rtk ruff check
rtk golangci-lint run

# Build tools (75-80% savings)
rtk cargo build
rtk next build
rtk pnpm list

# Container ops (80% savings)
rtk docker ps
rtk docker logs <container>
rtk kubectl get pods
rtk kubectl logs <pod>

When to Use RTK

Use rtk for:

• Commands that produce >100 lines of output
• Repeated operations (git status, test runs, lint checks)
• Any command in the supported command list below

Skip rtk for:

• Interactive commands (vim, nano)
• Commands already producing minimal output
• Heredocs or pipes (rtk auto-skips these)

Supported Commands

Version Control

• git - status, diff, log, add, commit, push, pull
• gh - pr list/view, issue list, run list

File Operations

• ls - directory listing
• cat/head/tail - file reading (rewritten to rtk read)
• rg/grep - search (rewritten to rtk grep)
• find - file search

Testing

• cargo test, npm test, vitest, jest, playwright, pytest, go test
• Shows failures only, collapses passing tests

Linting & Type Checking

• eslint, biome, tsc, prettier, ruff, golangci-lint, cargo clippy
• Groups errors by file/rule

Build Tools

• cargo build, next build, prisma generate
• Removes progress bars, focuses on errors

Package Management

• pnpm list, pip list, npm list
• Compact dependency trees

Containers & Orchestration

• docker ps/images/logs, docker compose ps
• kubectl get/logs
• Deduplicated logs, compact lists

Network & Logs

• curl - auto-detects JSON
• wget - strips progress bars
• docker logs, kubectl logs - deduplicates repeated lines

Output Compression Strategies

RTK applies four strategies per command type:

1. Smart Filtering - Removes comments, whitespace, boilerplate
2. Grouping - Aggregates similar items (files by dir, errors by type)
3. Truncation - Keeps relevant context, cuts redundancy
4. Deduplication - Collapses repeated log lines with counts

Reading Levels

bash

rtk read file.rs                    # Default: smart filtering
rtk read file.rs -l aggressive      # Signatures only (strips bodies)
rtk smart file.rs                   # 2-line heuristic summary

Error Handling

When a command fails, RTK saves the full unfiltered output:

text

FAILED: 2/15 tests
[full output: ~/.local/share/rtk/tee/1707753600_cargo_test.log]

Read the tee log file if you need the complete unfiltered output.

Token Savings Examples

Directory Listing

bash

# Standard ls -la (45 lines, ~800 tokens)
drwxr-xr-x 15 user staff 480 ... my-project/
-rw-r--r-- 1 user staff 1234 ...
...

# rtk ls (12 lines, ~150 tokens)
+-- src/ (8 files)
|   +-- main.rs
+-- Cargo.toml

Git Push

bash

# Standard git push (15 lines, ~200 tokens)
Enumerating objects: 5, done.
Counting objects: 100% (5/5), done.
...

# rtk git push (1 line, ~10 tokens)
ok main

Test Failures

bash

# Standard cargo test (200+ lines on failure)
running 15 tests
test utils::test_parse ... ok
...

# rtk test cargo test (~20 lines)
FAILED: 2/15 tests
test_edge_case: assertion failed
test_overflow: panic at utils.rs:18

Installation Verification

RTK binary should already be installed. Verify:

bash

rtk --version          # Should show version
rtk gain              # Show token savings stats

If not found, the binary needs to be installed in the container.

Advanced Usage

Ultra-compact mode

bash

rtk -u git status     # ASCII icons, inline format

Filtering

bash

rtk env -f AWS        # Show only AWS env vars

Summary mode

bash

rtk summary <long-command>  # Heuristic summary for unknown commands

Raw passthrough (with tracking)

bash

rtk proxy <command>   # Track usage without filtering

Configuration

RTK config file (if needed): ~/.config/rtk/config.toml

toml

[tracking]
database_path = "/path/to/custom.db"

[hooks]
exclude_commands = ["curl", "playwright"]  # Skip rewrite

[tee]
enabled = true           # Save raw output on failure
mode = "failures"        # "failures", "always", or "never"
max_files = 20          # Rotation limit

Auto-Rewrite Hook (Optional)

RTK supports auto-rewriting Bash commands via hooks (for Claude Code, OpenCode, Gemini CLI). This is optional and not required for manual usage.

If the hook is installed, commands like git status are automatically rewritten to rtk git status before execution.

Not applicable for this deployment - manual rtk prefixing is the expected pattern.

Analytics

Check token savings:

bash

rtk gain               # Summary stats
rtk gain --graph       # ASCII graph (last 30 days)
rtk gain --history     # Recent command history
rtk gain --daily       # Day-by-day breakdown

Troubleshooting

"rtk: command not found"

• Binary not in PATH or not installed
• Check: which rtk

Output still verbose

• Command not supported by rtk
• Use rtk proxy <command> to track unsupported commands

Need full output

• Read tee log file (shown in failure message)
• Or run command without rtk prefix

Reference

• GitHub: https://github.com/rtk-ai/rtk
• Documentation: https://www.rtk-ai.app
• Troubleshooting: https://github.com/rtk-ai/rtk/blob/master/docs/TROUBLESHOOTING.md