Caveman
A Claude Code plugin and cross-agent skill that makes the model reply in ultra-terse "caveman" style to cut output tokens while keeping technical accuracy.
Caveman is a Claude Code plugin and cross-agent skill that changes how the assistant writes answers: short, gruff, and low on filler. The current maintainer benchmark reports 65% fewer output tokens on average across ten prompts, with results ranging from 22% to 87%. The project explicitly warns that whole-session savings are lower and can be negative on work that was already terse. The tagline: why use many token when few do trick.
It is not a .NET- or language-specific skill; it is a response style and compression layer on top of whatever stack you are working on.
What it does
- Terser replies: drops hedging, pleasantries, and long intros; keeps commands, code, and fixes intact.
- Adjustable intensity: Lite (professional, less fluff), Full (default “caveman”), Ultra (maximum compression), plus optional 文言文 (wenyan) modes for an extreme written style.
- Extra commands (where supported) such as
caveman-commit(very short commit subjects),caveman-review(one-line review comments), andcaveman-compress(rewrites memory files likeCLAUDE.mdinto shorter text so the model reads fewer input tokens—with a human-readable backup alongside).
The skill targets output phrasing. Reasoning tokens and the roughly 1K to 1.5K input-token cost of the skill itself are separate, so measure your own workload before claiming savings. The optional local proxy is a different component that compresses input context.
Stop anytime with phrases like stop caveman or normal mode; start with /caveman, talk like caveman, or your host’s equivalent (e.g. Codex $caveman).
Install (common paths)
The simplest current install from the upstream README is:
npx skills add JuliusBrussee/cavemanHost-specific alternatives include:
| Host | One-liner (typical) |
|---|---|
| Claude Code | claude plugin marketplace add JuliusBrussee/caveman && claude plugin install caveman@caveman |
| Cursor | npx skills add JuliusBrussee/caveman -a cursor |
| Copilot (etc.) | npx skills add JuliusBrussee/caveman -a github-copilot |
| Gemini CLI | gemini extensions install https://github.com/JuliusBrussee/caveman |
| Many other agents | npx skills add JuliusBrussee/caveman (Vercel npx skills supports a long list) |
npx skills add only drops in the skill file for some IDEs—it may not add auto-start rules. For always-on behavior in Cursor and similar, the repo documents pasting a short “terse like caveman” block into rules or using their SessionStart / hook options where available. Claude Code’s plugin path includes hooks and optional statusline badge ([CAVEMAN], etc.) per their matrix.
Related projects
The same author also maintains cavemem (compressed cross-agent memory) and cavekit (spec-driven build loop). Both standalone repositories are now frozen; their active functionality has moved into Caveman.
Learn more
.NET Skills
The dotnet/skills repository, curated Agent Skills and plugins from the .NET team for better C# and .NET assistance in coding agents.
Andrej Karpathy skills
Karpathy-inspired Claude Code guidelines from multica-ai/andrej-karpathy-skills, think first, keep changes simple and surgical, and drive work with testable goals.