Caveman

Caveman makes AI agents talk like a caveman — ~75% fewer output tokens with zero loss of technical accuracy. "why use many token when few do trick."

Works across 30+ AI coding agents: Claude Code, OpenCode, Codex, Cursor, Gemini, Copilot, Windsurf, and more.

• Repo: github.com/JuliusBrussee/caveman
• License: MIT
• npm: caveman-shrink (MCP middleware)

Benefits

• ~65% fewer output tokens on average (range 22–87% across real-world benchmarks)
• ~46% fewer input tokens when compressing memory files (CLAUDE.md, project notes)
• No accuracy loss — brevity improved accuracy by 26 points in a March 2026 study
• Lifetime savings tracking with USD cost estimation

Quick Install

One-liner (auto-detects all agents):

curl -fsSL https://raw.githubusercontent.com/JuliusBrussee/caveman/main/install.sh | bash

Per-agent:

# Claude Code plugin
claude plugin marketplace add JuliusBrussee/caveman
claude plugin install caveman@caveman

# Codex CLI
npx skills add JuliusBrussee/caveman -a codex

# OpenCode
# Copy skill file manually or use the one-liner installer

# Cursor / Windsurf (always-on via rule file)
npx skills add JuliusBrussee/caveman -a cursor --with-init

Compression Levels

Level	Command	Token Reduction	Style
Lite	/caveman lite	~30%	Drops filler words
Full	/caveman	~65%	Default caveman style
Ultra	/caveman ultra	~75%	Telegraphic, minimal
Wenyan	/caveman wenyan	~80%	Classical Chinese

Turn off: Type normal mode or /caveman off.

Commands

/caveman                    # Activate full compression
/caveman ultra              # Maximum compression
/caveman lite               # Light mode

/caveman-commit             # Generate ≤50char conventional commit
/caveman-review             # One-line PR comments per change

/caveman-stats              # Token savings: "143k saved. ~$1.46"
/caveman-stats --share      # Tweetable stats

/caveman-compress CLAUDE.md # Rewrite memory file in caveman-speak

Cavecrew Subagents

Specialized subagents that talk in caveman by default (~60% fewer tokens than vanilla):

cavecrew-investigator    # Research and investigation
cavecrew-builder         # Implementation and coding
cavecrew-reviewer        # Code review and QA

caveman-shrink (MCP Middleware)

Wraps any MCP server to compress tool descriptions — reduces input tokens from tool listings:

npm install -g caveman-shrink
# Configure as middleware in your MCP server chain

Auto-Activation

Claude Code, Codex, and Gemini auto-activate Caveman every session via hooks. For other agents:

# Always-on via init rule file
npx skills add JuliusBrussee/caveman -a cursor --with-init

# Per-session manual activation
/caveman

Ecosystem

Tool	Purpose
caveman	Output compression (this)
caveman-code	Full terminal coding agent
cavemem	Cross-agent memory
cavekit	Spec-driven build loop
cavegemma	Gemma 4 31B fine-tuned on caveman pairs