caveman

why use many token when few do trick

Before/After • Install • Levels • Skills • Benchmarks • Evals

🪨 Caveman Ecosystem  ·  caveman talk less _{(you are here)}  ·  cavemem remember more  ·  cavekit build better

A Claude Code skill/plugin and Codex plugin that makes agent talk like caveman — cutting ~75% of output tokens while keeping full technical accuracy. Now with 文言文 mode, terse commits, one-line code reviews, and a compression tool that cuts ~46% of input tokens every session.

Based on the viral observation that caveman-speak dramatically reduces LLM token usage without losing technical substance. So we made it a one-line install.

Same fix. 75% less word. Brain still big.

Pick your level of grunt:

Same answer. You pick how many word.

┌─────────────────────────────────────┐
│  TOKENS SAVED          ████████ 75% │
│  TECHNICAL ACCURACY    ████████ 100%│
│  SPEED INCREASE        ████████ ~3x │
│  VIBES                 ████████ OOG │
└─────────────────────────────────────┘

• Faster response — less token to generate = speed go brrr
• Easier to read — no wall of text, just the answer
• Same accuracy — all technical info kept, only fluff removed (science say so)
• Save money — ~71% less output token = less cost
• Fun — every code review become comedy

Pick your agent. One command. Done.

Install once. Use in every session for that install target after that. One rock. That it.

Auto-activation is built in for Claude Code, Gemini CLI, and the repo-local Codex setup below. npx skills add installs the skill for other agents, but does not install repo rule/instruction files, so Caveman does not auto-start there unless you add the always-on snippet below.

claude plugin marketplace add JuliusBrussee/caveman
claude plugin install caveman@caveman

# macOS / Linux / WSL
bash <(curl -s https://raw.githubusercontent.com/JuliusBrussee/caveman/main/hooks/install.sh)

# Windows (PowerShell)
irm https://raw.githubusercontent.com/JuliusBrussee/caveman/main/hooks/install.ps1 | iex

[features]
codex_hooks = true

gemini extensions install https://github.com/JuliusBrussee/caveman

npx skills add JuliusBrussee/caveman           # auto-detect agent
npx skills add JuliusBrussee/caveman -a amp
npx skills add JuliusBrussee/caveman -a augment
npx skills add JuliusBrussee/caveman -a goose
npx skills add JuliusBrussee/caveman -a kiro-cli
npx skills add JuliusBrussee/caveman -a roo
# ... and many more

Terse like caveman. Technical substance exact. Only fluff die.
Drop: articles, filler (just/really/basically), pleasantries, hedging.
Fragments OK. Short synonyms. Code unchanged.
Pattern: [thing] [action] [reason]. [next step].
ACTIVE EVERY RESPONSE. No revert after many turns. No filler drift.
Code/commits/PRs: normal. Off: "stop caveman" / "normal mode".

Trigger with:

• /caveman or Codex $caveman
• "talk like caveman"
• "caveman mode"
• "less tokens please"

Stop with: "stop caveman" or "normal mode"

Classical Chinese literary compression — same technical accuracy, but in the most token-efficient written language humans ever invented.

Level stick until you change it or session end.

/caveman-commit — terse commit messages. Conventional Commits. ≤50 char subject. Why over what.

/caveman-review — one-line PR comments: L42: 🔴 bug: user null. Add guard. No throat-clearing.

/caveman-help — quick-reference card. All modes, skills, commands, one command away.

/caveman:compress <filepath> — caveman make Claude speak with fewer tokens. Compress make Claude read fewer tokens.

Your CLAUDE.md loads on every session start. Caveman Compress rewrites memory files into caveman-speak so Claude reads less — without you losing the human-readable original.

/caveman:compress CLAUDE.md

CLAUDE.md          ← compressed (Claude reads this every session — fewer tokens)
CLAUDE.original.md ← human-readable backup (you read and edit this)

Code blocks, URLs, file paths, commands, headings, dates, version numbers — anything technical passes through untouched. Only prose gets compressed. See the full caveman-compress README for details. Security note: Snyk flags this as High Risk due to subprocess/file patterns — it's a false positive.

Real token counts from the Claude API (reproduce it yourself):

Range: 22%–87% savings across prompts.

A March 2026 paper "Brevity Constraints Reverse Performance Hierarchies in Language Models" found that constraining large models to brief responses improved accuracy by 26 percentage points on certain benchmarks and completely reversed performance hierarchies. Verbose not always better. Sometimes less word = more correct.

Caveman not just claim 75%. Caveman prove it.

The evals/ directory has a three-arm eval harness that measures real token compression against a proper control — not just "verbose vs skill" but "terse vs skill". Because comparing caveman to verbose Claude conflate the skill with generic terseness. That cheating. Caveman not cheat.

# Run the eval (needs claude CLI)
uv run python evals/llm_run.py

# Read results (no API key, runs offline)
uv run --with tiktoken python evals/measure.py

If caveman save you mass token, mass money — leave mass star. ⭐

Three tools. One philosophy: agent do more with less.

They compose: cavekit orchestrates the build, caveman compresses what the agent says, cavemem compresses what the agent remembers. Install one, some, or all — each stands alone.

• Revu — local-first macOS study app with FSRS spaced repetition, decks, exams, and study guides. revu.cards

MIT — free like mass mammoth on open plain.