caveman-compress — Claude Code skill: compress memory files
Rewrites CLAUDE.md and todo files into terse caveman-speak so the model reads fewer input tokens. The source gets overwritten; a readable backup stays out of tree.
npx skills add JuliusBrussee/caveman --skill caveman-compress -a claude-codeWhat caveman-compress does
The skill rewrites memory files such as CLAUDE.md, todo lists or preference notes into a terse caveman style. Articles, filler words and hedges go, the meaning stays. Next session the model loads the compressed version, so fewer input tokens go into context.
Code fences, inline code, links, paths, commands, library names, versions, env vars and heading structure are copied exactly. The rules are strict, but read the output once anyway. Compressed text replaces the source file. The readable copy .original.md lands in a data dir ($XDG_DATA_HOME/caveman-compress/backups/, %LOCALAPPDATA% on Windows) rather than beside the source, so skill auto-loaders don't ingest it again.
Run python3 -m scripts from the directory holding SKILL.md. The script detects the file type, sends the text to the configured provider (claude CLI, Anthropic API or an OpenAI-compatible endpoint), validates the result and cherry-picks fixes. Up to 2 retries, then the source file stays untouched. Data leaves the machine, and names like .env, credentials, secrets are refused before anything is read. Text only: .md, .txt, .typ, .typst, .tex, extensionless. Worth installing when project memory has grown fat; skip it if part of that file can't leave your machine.
What it helps with
- compress a bloated
CLAUDE.mdbefore a long session - trim a todo file without losing items
- keep a readable copy of project memory before the overwrite
- check that code blocks and commands survived compression
- shrink a preferences file so it eats less context
Example prompts for the agent
- `/caveman-compress /Users/me/project/CLAUDE.md`
- compress my project memory in `CLAUDE.md` and keep the original
- run caveman-compress on `notes/todos.md`, leave the code blocks alone
How to install caveman-compress
1Skills CLI (Vercel)
npx skills add JuliusBrussee/caveman --skill caveman-compress -a claude-code2Manually: put the files in place
~/.claude/skills/caveman-compress/SKILL.mdCopy the whole skill folder; for one project use .claude/skills/caveman-compress/
1Skills CLI (Vercel)
npx skills add JuliusBrussee/caveman --skill caveman-compress -a codex2Manually: put the files in place
.agents/skills/caveman-compress/SKILL.mdFor all projects use ~/.agents/skills/
1Skills CLI (Vercel)
npx skills add JuliusBrussee/caveman --skill caveman-compress -a cursor2Manually: put the files in place
.cursor/skills/caveman-compress/SKILL.mdCursor also reads .agents/skills/ and .claude/skills/
1GitHub CLI
gh skill install JuliusBrussee/caveman caveman-compress2Manually: put the files in place
.github/skills/caveman-compress/SKILL.md1Skills CLI (Vercel)
npx skills add JuliusBrussee/caveman --skill caveman-compress -a gemini-cli2Platform CLI
gemini skills install https://github.com/JuliusBrussee/caveman --path skills/caveman-compressManually: put the files in place
.devin/skills/caveman-compress/SKILL.mdThe legacy .windsurf/skills/ path still works
Skills CLI (Vercel)
npx skills add JuliusBrussee/caveman --skill caveman-compress -a opencodeClaude.ai
Zip the folder and upload it in Settings → Capabilities → Skills
From the same set22
The whole set →Similar
Questions about caveman-compress
How do I install caveman-compress in Claude Code?
Run npx skills add JuliusBrussee/caveman --skill caveman-compress -a claude-code. The skill file ends up at ~/.claude/skills/caveman-compress/SKILL.md.
What does caveman-compress do?
It rewrites natural-language memory files into a compressed caveman style to cut input tokens. Code, paths, commands and heading structure stay as they were.
Where does the backup go?
The .original.md copy sits in a data dir, $XDG_DATA_HOME/caveman-compress/backups// or %LOCALAPPDATA% on Windows, not next to the source. The full file text is sent to the model provider, and names like .env or credentials are refused before reading.
Source text
SKILL.md · Apache-2.0
--- name: caveman-compress description: > Compress a memory file such as CLAUDE.md or a todo list into caveman format to save input tokens, keeping a readable backup. Sends the file's text to the configured model provider. Trigger: /caveman-compress. --- # Caveman Compress ## Purpose > **Data leaves the machine.** Compression sends the file's full text to the model provider that `scripts/compress.py` is configured for: the `claude` CLI, the Anthropic API, or an OpenAI-compatible endpoint. Files whose names look like secrets (`.env`, `credentials`, `secrets`, `.netrc`, …) are refused before they are read. Don't compress a file the provider shouldn't see. Compress natural language files (CLAUDE.md, todos, preferences) into caveman-speak to reduce input tokens. Compressed version overwrites original. Human-readable backup saved as `<filename>.original.md`, but NOT beside the source file — it lives in an out-of-tree data dir (`$XDG_DATA_HOME/caveman-compress/backups/<parent-dir-name>/`, or `%LOCALAPPDATA%\caveman-compress\backups\<parent-dir-name>\` on Windows) so skill auto-loaders don't re-ingest it as a live file. ## Trigger `/caveman-compress <filepath>` or when user asks to compress a memory file. **Requires an explicit filepath.** If the user pastes raw text instead of naming a file, do NOT improvise an inline compression — ask them for the filepath to compress, or offer to save the pasted text to a file first. Writing your own reasoning/commentary about the request into the compressed output (e.g. "User passed text directly, not a filepath...") is the exact failure this guards against — never let that leak into a saved file. ## Process 1. The compression scripts live in `scripts/` (adjacent to this SKILL.md). If the path is not immediately available, search for `scripts/__main__.py` next to this SKILL.md. 2. From the directory containing this SKILL.md, run: python3 -m scripts <absolute_filepath> 3. 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 4. 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 ## 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 — in the out-of-tree backup data dir (see Purpose), not beside the source file - Never compress FILE.original.md (skip it)
© JuliusBrussee · Apache-2.0 · JuliusBrussee/caveman