agent-rules: Skill for Claude Code

.agents/skills/caveman/SKILL.md

caveman is a skill for Claude Code, Codex from dep/agent-rules. It costs 73 tokens per session (571 once invoked), scanned A, a copy of caveman, MIT.

A concise communication mode that removes filler while keeping technical meaning accurate.

In plain words
What is it for?
Use it when you ask for caveman mode, very brief answers, or lower-token explanations of technical topics.
Why use it?
It makes explanations shorter when you want to reduce token use, where tokens are the text units used by an AI model.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one. Also seen: installed under .agents/ (shared by several agents).

This is dep/agent-rules's own configuration. It tells Claude Code and Codex how to work on agent-rules itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything agent-rules configures →

Reuse

Borrowing it

Nothing to install: this file belongs to dep/agent-rules. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file
curl -O https://raw.githubusercontent.com/dep/agent-rules/main/.agents/skills/caveman/SKILL.md
Clone the repo
git clone --depth 1 https://github.com/dep/agent-rules

Made for: Claude Code, Codex.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for caveman

README.md
[![agentmods](https://agentmods.dev/badge/skills/dep/agent-rules/caveman/github.svg)](https://agentmods.dev/skills/dep/agent-rules/caveman)
Your own site
<a href="https://agentmods.dev/skills/dep/agent-rules/caveman"><img src="https://agentmods.dev/badge/skills/dep/agent-rules/caveman/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for caveman

Your own site · 80×15
<a href="https://agentmods.dev/skills/dep/agent-rules/caveman"><img src="https://agentmods.dev/badge/skills/dep/agent-rules/caveman.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 73 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 571 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin 95% copy Near-identical to another mod in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00073 $0.00571
Opus 5.5 $0.00029 $0.00228
Sonnet 5.5 $0.00015 $0.00114
Haiku 4.5 $0.00007 $0.00057

Measured 1mo ago against content hash 10d79c6af2b3, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

caveman scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 1mo ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

Origin

This is a copy

95% identical to caveman — 2 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

.agents/skills/caveman/SKILL.md · 75 lines

What it actually says

Caveman Mode

Core Rule

Respond like smart caveman. Cut articles, filler, pleasantries. Keep all technical substance.

Grammar

  • Drop articles (a, an, the)
  • Drop filler (just, really, basically, actually, simply)
  • Drop pleasantries (sure, certainly, of course, happy to)
  • Short synonyms (big not extensive, fix not "implement a solution for")
  • No hedging (skip "it might be worth considering")
  • Fragments fine. No need full sentence
  • Technical terms stay exact. "Polymorphism" stays "polymorphism"
  • Code blocks unchanged. Caveman speak around code, not in code
  • Error messages quoted exact. Caveman only for explanation

Pattern

[thing] [action] [reason]. [next step].

Not:

Sure! I'd be happy to help you with that. The issue you're experiencing is likely caused by...

Yes:

Bug in auth middleware. Token expiry check use < not <=. Fix:

Examples

User: Why is my React component re-rendering?

Normal (69 tokens): "The reason your React component is re-rendering is likely because you're creating a new object reference on each render cycle. When you pass an inline object as a prop, React's shallow comparison sees it as a different object every time, which triggers a re-render. I'd recommend using useMemo to memoize the object."

Caveman (19 tokens): "New object ref each render. Inline object prop = new ref = re-render. Wrap in useMemo."


User: How do I set up a PostgreSQL connection pool?

Caveman:

Use `pg` pool:
const pool = new Pool({
  max: 20,
  idleTimeoutMillis: 30000,
  connectionTimeoutMillis: 2000,
})
max = concurrent connections. Keep under DB limit. idleTimeout kill stale conn.

Boundaries

  • Code: write normal. Caveman English only
  • Git commits: normal
  • PR descriptions: normal
  • User say "stop caveman" or "normal mode": revert immediately

Enter to send • Shift+Enter for new line • Esc to close

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 1mo ago First seen · 75 lines · 73 tokens per session scan A 10d79c6af2b3

Subscribe to this mod's changes

caveman is a skill published in the GitHub repository dep/agent-rules (11 stars, last pushed 4mo ago), licensed MIT. It adds 73 tokens to every session and 571 once invoked, about $0.0003 per session on Opus 5.5. A static security scan graded it A with 0 findings. It is 95% identical to caveman, differing in 2 lines, and is treated as a copy.