Borrowing it
Nothing to install: this file belongs to pomagrenate/ice_age. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/pomagrenate/ice_age/main/CLAUDE.mdgit clone --depth 1 https://github.com/pomagrenate/ice_ageWrote 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.
[](https://agentmods.dev/instructions/pomagrenate/ice_age/claude-md)<a href="https://agentmods.dev/instructions/pomagrenate/ice_age/claude-md"><img src="https://agentmods.dev/badge/instructions/pomagrenate/ice_age/claude-md.svg" alt="Measured on agentmods" height="20"></a>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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.03141 | $0.03141 |
| Opus 5 | $0.01571 | $0.01571 |
| Sonnet 5 | $0.00628 | $0.00628 |
| Haiku 4.5 | $0.00314 | $0.00314 |
Grade B, and why
ice_age CLAUDE.md scanned grade B with 1 finding 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 7d 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.
Reads agent configuration directoriesmediumAgent snooping
.claude/, .codex/, .gemini/ hold keys, settings and other credentials a mod has no legitimate need for.
**Standalone install** — `hooks/install.sh` (macOS/Linux) or `hooks/install.ps1` (Windows) copies hook files into `~/.claude/hooks/` and patches `~/.claude/settings.json` to register SessionStart and UserPromptSubmit hoo How it starts
The opening of the file, as written. The whole thing — 217 lines — stays where its author put it; the contents beside it link to each section on GitHub.
CLAUDE.md — iceage
README is a product artifact
README = product front door. Non-technical people read it to decide if iceage worth install. Treat like UI copy.
Rules for any README change:
- Readable by non-AI-agent users. If you write "SessionStart hook injects system context," invisible to most — translate it.
- Keep Before/After examples first. That the pitch.
- Install table always complete + accurate. One broken install command costs real user.
- What You Get table must sync with actual code. Feature ships or removed → update table.
- Preserve voice. Iceage speak in README on purpose. "Brain still big." "Cost go down forever." "One rock. That it." — intentional brand. Don't normalize.
- Benchmark numbers from real runs in
benchmarks/andevals/. Never invent or round. Re-run if doubt. - Adding new agent to install table → add detail block in
<details>section below. - Readability check before any README commit: would non-programmer understand + install within 60 seconds?
Project overview
Iceage makes AI coding agents respond in compressed iceage-style prose — cuts ~65-75% output tokens, full technical accuracy. Ships as Claude Code plugin, Codex plugin, Gemini CLI extension, agent rule files for Cursor, Windsurf, Cline, Copilot, 40+ others via npx skills.
File structure and what owns what
Single source of truth files — edit only these
| File | What it controls |
|---|---|
skills/iceage/SKILL.md |
Iceage behavior: intensity levels, rules, wenyan mode, auto-clarity, persistence. Only file to edit for behavior changes. |
rules/iceage-activate.md |
Always-on auto-activation rule body. CI injects into Cursor, Windsurf, Cline, Copilot rule files. Edit here, not agent-specific copies. |
skills/iceage-commit/SKILL.md |
Iceage commit message behavior. Fully independent skill. |
skills/iceage-review/SKILL.md |
Iceage code review behavior. Fully independent skill. |
skills/iceage-help/SKILL.md |
Quick-reference card. One-shot display, not a persistent mode. |
skills/iceage-batch/SKILL.md |
Batch compress behavior. Fully independent skill. |
skills/compress/SKILL.md |
Compress sub-skill behavior. |
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.
- 7d ago First seen · 217 lines · 3,141 tokens per session scan B 2aad8e7592fa
ice_age CLAUDE.md is an instructions file published in the GitHub repository pomagrenate/ice_age (2 stars, last pushed 19d ago), licensed Apache-2.0. It adds 3,141 tokens to every session, about $0.0157 per session on Opus 5. A static security scan graded it B with 1 finding (reads agent configuration directories). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.
Other instructions, from other repositories
weld cpp.instructions.md
C++ naming and structure guidance.
weld testing.instructions.md
Test guidance for implementation changes.
weld copilot-instructions.md
Copilot instructions for configflux/weld: Use @docs/architecture/principles.md for architecture-sensitive changes.
codex AGENTS.md
AGENTS.md instructions for openai/codex, covering rust/codex-rs, the codex-core crate, code review rules, crate api surface and model visible context.
vscode buildNext.instructions.md
Working notes and architecture documentation for the new esbuild-based build system in build/next. Use when making changes to the new build pipeline (transpile/bundle commands, NLS plugin, source-map handling, resource copying, or self-hosting watch tasks).
next.js AGENTS.md
AGENTS.md instructions for vercel/next.js, covering next.js development guide, codebase structure, monorepo overview, core package: packages/next and other important packages.