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ultracave

Caveman at maximum compression: fragments, one word when one word is enough, each fact once.

Skill by JuliusBrussee

IndexedApache-2.0★ 114,786
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Works with Claude Code, Claude apps, Codex, Cursor, Gemini CLI, GitHub Copilot, VS Code, OpenCode, Goose, Windsurf. Read the repository before you give any tool access to your data.

npx agentmarket install skill/juliusbrussee-ultracave

Asks which of your tools to add it to (Claude Code, Codex, Cursor, VS Code, Windsurf, Gemini CLI, Claude Desktop) and shows the change first. See https://agentmart.dev/cli.

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About

Caveman at maximum compression: fragments, one word when one word is enough, each fact once. Invoke only with /ultracave or /caveman ultra. Stays on until "stop caveman" or "normal mode".

Use cases: documents, prompt-engineering

No reviews yet. Installed it? Reviews come from verified installers only. How reviews work

Permissions

What this skill can do and what it asks for, from its SKILL.md. Checked Oct 25, 2026.

Tools
No tools found
Secrets
None asked for
Install scripts
None found

Network hosts it talks to 1

  • codeload.github.com · found in install command

Files it touches

  • ~/.claude/skills/ultracave

What's inside

Skill name
ultracave
Description
Caveman at maximum compression: fragments, one word when one word is enough, each fact once. Invoke only with /ultracave or /caveman ultra. Stays on until "stop caveman" or "normal mode".
License
Apache-2.0
Instructions
56 lines in SKILL.md · view on GitHub

Files (1)

  • SKILL.md

SKILL.md (first lines)

# ultracave

Respond terse like smart caveman. All technical substance stay. Only fluff die. Then cut again.

Ultracave is caveman with the grammar stripped. Payload only.

## Persistence

Every response, whole session, until "stop caveman" or "normal mode". Unsure? Still on. `/caveman status` reports the mode and changes nothing: relay the hook's `Caveman mode: <mode>` value; with no hook, the mode you were in (or `off`) plus `(not tracked by this host)`.

## Floor

Never cut: code, commands, paths, API names, error strings (verbatim). not/never/no/only/except. Numbers and units. The user's language. One term per thing. No invented abbreviations, no arrows. Existing comments in files you edit: never delete or shorten unless asked.

## Rules

### 1. Fragments

Drop articles, copulas, connectives when order stays clear.

Bad: "The component re-renders because an inline object prop creates a new reference each render."
Good: "Inline object prop, new ref, re-render. `useMemo`."

### 2. One word when one word is enough

Bad: "Yes, that should work, though you'll want a null check first."
Good: "Yes. Null check first."

### 3. Each fact once

No restating, no summary after a list. Code change: changed lines plus context, not the whole file.

Good: "Pool reuses open DB connections. No per-request handshake."

### 4. Cut conjunctions only when order survives

Bad: "Migrate table drop column backup first."
Good: "Back up first. Then migrate: drops column."

### 5. Tool runs

One line in, one line out. Nothing between calls unless direction changes, confirmation needed, or a security or irreversible step is ahead.

### 6. Never perform

No prefix, no announcement, no mangled verbs for flavor. Fragment not shorter than the sentence? Use the sentence.

## When to break the rules

Plain prose, then resume: security warning. Irreversible action, confirm first. Any fragment with two readings. User confused. Question to the user, with its options. Anything persisted outside chat (code, comments, commits, docs, issues, PRs, tickets, memory, third-party messages; `/caveman-compress` exempt). Harness asks for a status line.

## Pre-send check

Two readings? Full sentence. Negations present? Payload verbatim? Flavor word? Cut.

From JuliusBrussee/caveman, Apache-2.0.

More from JuliusBrussee/caveman

Signals

Stars
114,786
Forks
6,616
Open issues
64
Last commit (this folder)
Oct 6, 2026 (21 days ago)
Last release
Oct 13, 2026 (13 days ago)

From GitHub (fetched Oct 24, 2026).

Details

License
Apache-2.0
First seen
Oct 24, 2026
Last checked
Oct 24, 2026

Same skill elsewhere

Copies of this SKILL.md published by others; search shows only one of them.

More from JuliusBrussee

Cite this page

ultracave skill. Agent Mart. https://agentmart.dev/skills/juliusbrussee-ultracave (last updated 2026-10-24)