Using Agent Skills
addyosmani/agent-skills
Meta-skill for choosing which workflow skill fits the task at hand, plus always-on habits: surface assumptions, stop on confusion, push back, keep it simple and stay in scope.
Compress natural language memory files (CLAUDE.md, todos, preferences) into caveman format to save input tokens.
Install Caveman Compress
$ npx skills add vishiri/fantasia-archive --skill caveman-compress -a claude-codeProject install by default; add -g for ~/.claude/skills/.
$ gh skill install vishiri/fantasia-archive caveman-compress --agent claude-codeProject scope by default; add --scope user for a personal install. Needs GitHub CLI 2.90.0 or later (public preview).
$ git clone --depth 1 https://github.com/vishiri/fantasia-archive.git skills-src && mkdir -p .claude/skills && cp -r skills-src/.agents/skills/caveman-compress .claude/skills/caveman-compress && rm -rf skills-srcUse ~/.claude/skills/ instead of .claude/skills for a personal install. The folder must contain SKILL.md.
Claude Code skills documentation · loads skills from .claude/skills/
Install the "caveman-compress" agent skill from https://github.com/vishiri/fantasia-archive/tree/master/.agents/skills/caveman-compress into .claude/skills/caveman-compress/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "caveman-compress", then confirm the skill loads.Claude Code copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$skill-installer install https://github.com/vishiri/fantasia-archive/tree/master/.agents/skills/caveman-compressType this inside Codex. $skill-installer <name> installs a curated skill from openai/skills. The installer writes to $CODEX_HOME/skills (default ~/.codex/skills). Restart Codex if the skill does not show up.
$ npx skills add vishiri/fantasia-archive --skill caveman-compress -a codexProject install goes to .agents/skills/; add -g for ~/.codex/skills/.
$ gh skill install vishiri/fantasia-archive caveman-compress --agent codexProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/vishiri/fantasia-archive.git skills-src && mkdir -p .agents/skills && cp -r skills-src/.agents/skills/caveman-compress .agents/skills/caveman-compress && rm -rf skills-srcUse ~/.agents/skills/ instead of .agents/skills for a personal install.
Codex skills documentation · loads skills from .agents/skills/
Install the "caveman-compress" agent skill from https://github.com/vishiri/fantasia-archive/tree/master/.agents/skills/caveman-compress into .agents/skills/caveman-compress/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "caveman-compress", then confirm the skill loads.Codex copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ npx skills add vishiri/fantasia-archive --skill caveman-compress -a cursorProject install goes to .agents/skills/; add -g for ~/.cursor/skills/.
$ gh skill install vishiri/fantasia-archive caveman-compress --agent cursorProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/vishiri/fantasia-archive.git skills-src && mkdir -p .cursor/skills && cp -r skills-src/.agents/skills/caveman-compress .cursor/skills/caveman-compress && rm -rf skills-srcUse ~/.cursor/skills/ instead of .cursor/skills for a personal install.
Cursor skills documentation · loads skills from .cursor/skills/, .agents/skills/, .claude/skills/, .codex/skills/
Install the "caveman-compress" agent skill from https://github.com/vishiri/fantasia-archive/tree/master/.agents/skills/caveman-compress into .cursor/skills/caveman-compress/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "caveman-compress", then confirm the skill loads.Cursor copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ gemini skills install https://github.com/vishiri/fantasia-archive.git --path .agents/skills/caveman-compress--scope user (default) or --scope workspace; --path is the subfolder of the repo that holds the skill; --consent skips the security confirmation prompt.
$ npx skills add vishiri/fantasia-archive --skill caveman-compress -a gemini-cliProject install goes to .agents/skills/; add -g for ~/.gemini/skills/.
$ gh skill install vishiri/fantasia-archive caveman-compress --agent gemini-cliProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/vishiri/fantasia-archive.git skills-src && mkdir -p .gemini/skills && cp -r skills-src/.agents/skills/caveman-compress .gemini/skills/caveman-compress && rm -rf skills-srcUse ~/.gemini/skills/ instead of .gemini/skills for a personal install, then run /skills reload.
Gemini CLI skills documentation · loads skills from .gemini/skills/, .agents/skills/
Install the "caveman-compress" agent skill from https://github.com/vishiri/fantasia-archive/tree/master/.agents/skills/caveman-compress into .gemini/skills/caveman-compress/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "caveman-compress", then confirm the skill loads.Gemini CLI copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ gh skill install vishiri/fantasia-archive caveman-compressInstalls for Copilot at project scope by default; add --scope user for a personal install. Preview a skill first with gh skill preview. Needs GitHub CLI 2.90.0 or later (public preview).
$ npx skills add vishiri/fantasia-archive --skill caveman-compress -a github-copilotProject install goes to .agents/skills/; add -g for ~/.copilot/skills/.
$ git clone --depth 1 https://github.com/vishiri/fantasia-archive.git skills-src && mkdir -p .github/skills && cp -r skills-src/.agents/skills/caveman-compress .github/skills/caveman-compress && rm -rf skills-srcUse ~/.copilot/skills/ instead of .github/skills for a personal install. Commit .github/skills so cloud agent and code review can use it.
GitHub Copilot skills documentation · loads skills from .github/skills/, .claude/skills/, .agents/skills/
Install the "caveman-compress" agent skill from https://github.com/vishiri/fantasia-archive/tree/master/.agents/skills/caveman-compress into .github/skills/caveman-compress/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "caveman-compress", then confirm the skill loads.GitHub Copilot copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ npx skills add vishiri/fantasia-archive --skill caveman-compress -a opencodeOpenCode documents no install command of its own. Project install goes to .agents/skills/; add -g for ~/.config/opencode/skills/.
$ gh skill install vishiri/fantasia-archive caveman-compress --agent opencodeProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/vishiri/fantasia-archive.git skills-src && mkdir -p .opencode/skills && cp -r skills-src/.agents/skills/caveman-compress .opencode/skills/caveman-compress && rm -rf skills-srcUse ~/.config/opencode/skills/ instead of .opencode/skills for a personal install.
OpenCode skills documentation · loads skills from .opencode/skills/, .claude/skills/, .agents/skills/
Install the "caveman-compress" agent skill from https://github.com/vishiri/fantasia-archive/tree/master/.agents/skills/caveman-compress into .opencode/skills/caveman-compress/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "caveman-compress", then confirm the skill loads.OpenCode copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
Facts
- Skill name
caveman-compress- GitHub stars
- 409
- Used in
- 9 other repos
- Token cost
- ~1.1k tokens
- SKILL.md length
- 559 words
- Files
- 10 (incl. scripts)
- Skills in repo
- 35
- Repo updated
- First seen
- Licence
- GPL-3.0
At a glance
Compress natural language memory files (CLAUDE.md, todos, preferences) into caveman format to save input tokens.
- Works in 2 steps: The compression scripts live in scripts/… → From the directory containing this…
- Tasks that involve Agent instruction files
- SKILL.md covers Purpose, Trigger, Process and Compression Rules, plus 2 more sections
- Runs Python scripts from its folder; calls npm, git and docker
What it does
Caveman Compress is an agent skill from vishiri/fantasia-archive. Compress natural language memory files (CLAUDE.md, todos, preferences) into caveman format to save input tokens. Preserves all technical substance, code, URLs, and structure. Compressed version overwrites the original file. Human-readable backup saved as FILE.original.md. Trigger: /caveman-compress FILEPATH or "compress memory file"
Its SKILL.md is about 1.1k tokens, which your agent loads only when the skill is triggered. The skill folder holds 10 other files, including scripts (for example `README.md`, `SECURITY.md` and `scripts/__init__.py`).
It sits in Agent Workflows, covering Agent instruction files. The repository describes itself as: A world-builder's best friend! The licence is GPL-3.0.
When your agent uses it
- Tasks that involve Agent instruction files
Example prompts
- “compress memory file”
- “/caveman-compress”
Requirements
- Python 3
- Node.js
- Docker
Workflow steps
2 steps, taken from the first numbered list in SKILL.md.
- The compression scripts live in scripts/ (adjacent to this SKILL.md). If the path is not immediately available, search for scripts/main.py…
- From the directory containing this SKILL.md, run
What it can do on your machine
Read from SKILL.md and the folder at commit 26d4648. It shows what the files ask for, not the result of running them.
Tool permissions
Pre-approves nothing: there is no allowed-tools line, so your agent's usual permission prompts apply.
From allowed-tools in the SKILL.md frontmatter.
Runs code
Ships 7 files in scripts/ (Python), which the agent can run.
Shell commands in SKILL.md call:
npmgitdocker
From the folder's file list and the shell code blocks in SKILL.md.
Network
No URLs in SKILL.md. Its commands use npm, git and docker, which can reach the network depending on how they are called.
From URLs in SKILL.md, links to its own repository left out.
Credentials
Names no API keys, tokens, secrets or passwords.
From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.
Context cost
Caveman Compress loads about 1.1k tokens when it runs. Until then it costs about 88 tokens; SKILL.md has 559 words of instructions outside code blocks.
Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.
Safety
Auto-check: notes
The automated check noted patterns worth knowing about, such as sudo or a known installer.
- NoteMentions a .env fileSKILL.md:107
py, .js, .ts, .json, .yaml, .yml, .toml, .env, .lock, .css, .html, .xml, .sql, .sh
Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); the scripts in this folder are not scanned.
SKILL.md
The full file from vishiri/fantasia-archive at commit 26d4648, republished under its GPL-3.0 licence (© vishiri). 559 words, ~1,132 tokens.
Download SKILL.mdSave it as
.claude/skills/caveman-compress/SKILL.md (or your agent's skills folder). This skill also uses 9 other files; get the full folder from GitHub.- name
- caveman-compress
- description
- Compress natural language memory files (CLAUDE.md, todos, preferences) into caveman format to save input tokens. Preserves all technical substance, code, URLs, and structure. Compressed version overwrites the original file. Human-readable backup saved as FILE.original.md. Trigger: /caveman-compress FILEPATH or "compress memory file"
Caveman Compress
Purpose
Compress natural language files (CLAUDE.md, todos, preferences) into caveman-speak to reduce input tokens. Compressed version overwrites original. Human-readable backup saved as <filename>.original.md.
Trigger
/caveman-compress <filepath> or when user asks to compress a memory file.
Process
The compression scripts live in
scripts/(adjacent to this SKILL.md). If the path is not immediately available, search forscripts/__main__.pynext to this SKILL.md.From the directory containing this SKILL.md, run:
python3 -m scripts <absolute_filepath>
- The CLI will:
- detect file type (no tokens)
- call Claude to compress
- validate output (no tokens)
- if errors: cherry-pick fix with Claude (targeted fixes only, no recompression)
- retry up to 2 times
- if still failing after 2 retries: report error to user, leave original file untouched
- Return result to user
Compression Rules
Remove
- Articles: a, an, the
- Filler: just, really, basically, actually, simply, essentially, generally
- Pleasantries: "sure", "certainly", "of course", "happy to", "I'd recommend"
- Hedging: "it might be worth", "you could consider", "it would be good to"
- Redundant phrasing: "in order to" → "to", "make sure to" → "ensure", "the reason is because" → "because"
- Connective fluff: "however", "furthermore", "additionally", "in addition"
Preserve EXACTLY (never modify)
- Code blocks (fenced ``` and indented)
- Inline code (
backtick content) - URLs and links (full URLs, markdown links)
- File paths (
/src/components/...,./config.yaml) - Commands (
npm install,git commit,docker build) - Technical terms (library names, API names, protocols, algorithms)
- Proper nouns (project names, people, companies)
- Dates, version numbers, numeric values
- Environment variables (
$HOME,NODE_ENV)
Preserve Structure
- All markdown headings (keep exact heading text, compress body below)
- Bullet point hierarchy (keep nesting level)
- Numbered lists (keep numbering)
- Tables (compress cell text, keep structure)
- Frontmatter/YAML headers in markdown files
Compress
- Use short synonyms: "big" not "extensive", "fix" not "implement a solution for", "use" not "utilize"
- Fragments OK: "Run tests before commit" not "You should always run tests before committing"
- Drop "you should", "make sure to", "remember to" — just state the action
- Merge redundant bullets that say the same thing differently
- Keep one example where multiple examples show the same pattern
CRITICAL RULE:
Anything inside ... must be copied EXACTLY.
Do not:
- remove comments
- remove spacing
- reorder lines
- shorten commands
- simplify anything
Inline code (...) must be preserved EXACTLY.
Do not modify anything inside backticks.
If file contains code blocks:
- Treat code blocks as read-only regions
- Only compress text outside them
- Do not merge sections around code
Show full SKILL.md (171 more words)Show less
Pattern
Original:
You should always make sure to run the test suite before pushing any changes to the main branch. This is important because it helps catch bugs early and prevents broken builds from being deployed to production.
Compressed:
Run tests before push to main. Catch bugs early, prevent broken prod deploys.
Original:
The application uses a microservices architecture with the following components. The API gateway handles all incoming requests and routes them to the appropriate service. The authentication service is responsible for managing user sessions and JWT tokens.
Compressed:
Microservices architecture. API gateway route all requests to services. Auth service manage user sessions + JWT tokens.
Boundaries
- ONLY compress natural language files (.md, .txt, .typ, .typst, .tex, extensionless)
- NEVER modify: .py, .js, .ts, .json, .yaml, .yml, .toml, .env, .lock, .css, .html, .xml, .sql, .sh
- If file has mixed content (prose + code), compress ONLY the prose sections
- If unsure whether something is code or prose, leave it unchanged
- Original file is backed up as FILE.original.md before overwriting
- Never compress FILE.original.md (skip it)
© vishiri, GPL-3.0. Rendered from Markdown: HTML in the file is shown as text, images as links, and headings moved down two levels. Raw file
Files
SKILL.md and 9 other files (scripts) in .agents/skills/caveman-compress of vishiri/fantasia-archive.
- SKILL.md
- README.md
- SECURITY.md
- scripts/__init__.py
- scripts/__main__.py
- scripts/benchmark.py
- scripts/cli.py
- scripts/compress.py
- scripts/detect.py
- scripts/validate.py
Open the folder on GitHubat commit 26d4648
Used in 9 other repositories
We found 15 copies of this SKILL.md (exact, near-identical or edited) in other folders, from 9 other GitHub owners. This page covers the copy in vishiri/fantasia-archive, which our catalogue first saw on October 7, 2026.
- rishighan/threetwo.agents/skills/compress.agents/skills/caveman-compress
- jjmartres/opencodeopencode/skills/caveman-compress
- vvedantb/eva.claude/skills/compress.agents/skills/caveman-compress+1 more
- kubestellar/console.agents/skills/caveman-compress
- stevesolun/ctximported-skills/julius-caveman/skills/caveman-compress
- shortcuts/locationjoystick.agents/skills/caveman-compress
- aiskillstore/marketplaceskills/juliusbrussee/compressskills/juliusbrussee/caveman-compress
- HoangNguyen0403/agent-skills-standard.agents/skills/caveman-compress
- fmflurry/settings-opencodeskills/compress.claude/skills/compress+1 more
Compare with similar skills
Caveman Compress next to the 5 skills that share the most tags, products or categories with it. Stars are the repository's; “used in” counts other GitHub owners with a copy.
| Skill | Stars | Used in | Tokens | Auto-check | Licence | Repo updated |
|---|---|---|---|---|---|---|
| Caveman Compress this skillvishiri/fantasia-archive | 409 | 9 repos | ~1.1k | Automated safety check: Notes | GPL-3.0 | |
| Using Agent Skillsaddyosmani/agent-skills | 104k | 4 repos | ~2.4k | Automated safety check: Pass | MIT | |
| Claude ReflectBayramAnnakov/claude-reflect | 1.8k | 2 repos | ~627 | Automated safety check: Pass | MIT | |
| Neat-Freak Knowledge CloseoutKKKKhazix/khazix-skills | 21k | — | ~1.9k | Automated safety check: Pass | MIT | |
| Writing For Agentsbestofjs/bestofjs | 3.1k | 18 repos | ~2.7k | Automated safety check: Pass | MIT | |
| Task Observerrebelytics/one-skill-to-rule-them-all | 3.2k | 1 repos | ~11k | Automated safety check: Pass | CC-BY-4.0 |
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Brings project docs, agent rule files, authorized memory and leftover workspace files back in line with what the code and runtime actually do at the end of a work session.
Writing For Agents
bestofjs/bestofjs
Writing documents for agents. An agent skill from bestofjs/bestofjs.
Task Observer
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Monitors task execution for skill improvement opportunities.
- Official
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Related
Categories
Questions about Caveman Compress
What does Caveman Compress do?
Compress natural language memory files (CLAUDE.md, todos, preferences) into caveman format to save input tokens. Caveman Compress is an agent skill from vishiri/fantasia-archive.md, todos, preferences) into caveman format to save input tokens.
When should I use Caveman Compress?
Caveman Compress fits situations like: tasks that involve Agent instruction files.
How do I install Caveman Compress in Claude Code?
Run `npx skills add vishiri/fantasia-archive --skill caveman-compress -a claude-code`. Or copy the skill folder (.agents/skills/caveman-compress in vishiri/fantasia-archive) into .claude/skills/caveman-compress in your project. Claude Code loads it when a task matches its description.
How do I install Caveman Compress in Codex?
Run `npx skills add vishiri/fantasia-archive --skill caveman-compress -a codex`. Or copy the skill folder (.agents/skills/caveman-compress in vishiri/fantasia-archive) into .agents/skills/caveman-compress in your project. Codex loads it when a task matches its description.
Can I use Caveman Compress in Cursor, Gemini CLI or GitHub Copilot?
Cursor, Gemini CLI, GitHub Copilot and OpenCode also load SKILL.md folders. With the skills CLI, run `npx skills add vishiri/fantasia-archive --skill caveman-compress -a cursor` (or -a gemini-cli, github-copilot or opencode for the others). To copy it by hand, put the folder in .cursor/skills/caveman-compress, .gemini/skills/caveman-compress, .github/skills/caveman-compress and .opencode/skills/caveman-compress in your project.
What does Caveman Compress need to run?
Going by SKILL.md and its folder, Caveman Compress needs Python for the scripts in its folder and the command-line tools its instructions call (npm, git and docker). Our summary lists: Python 3; Node.js; Docker.
Does Caveman Compress access the network?
SKILL.md contains no URLs. Its commands use npm, git and docker, which can reach the network depending on how they are called. This is read from the text; nothing was executed.
Is Caveman Compress safe to install?
Our automated static check of SKILL.md found notes only (mentions a .env file), nothing it rates as a warning. It is not a guarantee. The check reads SKILL.md only: the scripts in the folder are not scanned, so read them before running anything.
What licence does Caveman Compress use?
Caveman Compress is published under the GPL-3.0 licence (the repository's licence). It allows redistribution, so the full SKILL.md is shown on this page.
How many tokens does Caveman Compress use?
About 1.1k tokens (SKILL.md is roughly 4.5k characters). Agents keep only the skill's name and description in context until a task matches; then they load SKILL.md in full.
What are the alternatives to Caveman Compress?
Skills that share tags, products or a category with Caveman Compress: Using Agent Skills (addyosmani/agent-skills, 104k stars), Claude Reflect (BayramAnnakov/claude-reflect, 1.8k stars), Neat-Freak Knowledge Closeout (KKKKhazix/khazix-skills, 21k stars) and Writing For Agents (bestofjs/bestofjs, 3.1k stars). The comparison table on this page puts their stars, adoption, token cost, safety result and licence side by side.
Who maintains Caveman Compress?
vishiri (a GitHub user) maintains it in vishiri/fantasia-archive, which has 409 GitHub stars. The repository holds 35 skills in this directory. The repository was last updated on October 7, 2026.
Source: vishiri/fantasia-archive on GitHub. Facts on this page come from the repository at the commit we read; the author's words are quoted as theirs.