Lean Ctx

Q: What is a Claude Code skill and how does the Lean Ctx skill fit in?

A Claude Code skill is a SKILL.md file that lives under ~/.claude/skills/<name>/ and tells the Claude Code CLI agent how to perform a specific task (instructions, prompts, allowed tools). Skills are auto-discovered at session start. Lean Ctx is one of 67,000+ skills indexed in the open ClaudSkills catalog, classified under the Product category. Learn more at https://claudskills.com/learn/what-is-skill-md/.

Category: Product · Sub-category: product-misc · Last updated: 2026-05-21

Context Runtime for AI Agents — 48 MCP tools, 10 read modes, 90+ shell patterns, tree-sitter AST for 18 languages. Compresses LLM context by up to 99%. Use when reading files, running shell commands, searching code, or exploring directories. Auto-installs if not present.

From the source SKILL.md

LeanCTX optimizes LLM context through 48 MCP tools, 90+ shell compression patterns, and tree-sitter AST parsing for 18 languages. It provides adaptive file reading, cross-session memory (CCP), task-conditioned relevance scoring, and a feedback loop for learning optimal compression.

What this skill does

Lean Ctx is a community-contributed Claude Code skill in the product-misc sub-category. It ships as a SKILL.md file that Claude Code auto-discovers under ~/.claude/skills/lean-ctx/ and loads when your prompt matches the skill's trigger.

When to invoke it: Use when reading files, running shell commands, searching code, or exploring directories. Auto-installs if not present.

Who uses this skill

The Lean Ctx Claude Code skill is built for product managers, product designers, and cross-functional teams planning, shipping, and measuring product features. It's part of ClaudSkills (also referred to as Claude Skills or Claude Code Skills) — the open community-curated registry of 116,000+ SKILL.md files for Anthropic's Claude Code agent and the wider Claude ecosystem (Claude API, Claude Agent SDK).

How to install

Free

Manual install (2 steps)

mkdir -p ~/.claude/skills/lean-ctx
curl -L https://claudskills.com/skills/lean-ctx/SKILL.md \
  -o ~/.claude/skills/lean-ctx/SKILL.md

Or just download SKILL.md directly and drop it into ~/.claude/skills/lean-ctx/. Claude Code auto-discovers it on next session.

Skills live at ~/.claude/skills/lean-ctx/SKILL.md on macOS/Linux, or %USERPROFILE%\.claude\skills\lean-ctx\SKILL.md on Windows. See the full install guide for step-by-step instructions.

📱 Install from your phone or desktop Telegram

Open @claudskills_bot on Telegram, tap Open Desktop App, and the desktop app installs this skill for you. Or share the bot link with a colleague — they get the same one-tap install. Learn more →

Pro

One-click install via the desktop app

The ClaudSkills desktop app installs any skill directly into ~/.claude/skills/ with one click — no terminal required. Pro starts at $9/mo or $149 lifetime.

Pro

For the full experience including quality scoring and one-click install features for each skill — upgrade to Pro.

See pricing → Download desktop app

Frequently asked questions

How do I install the Lean Ctx Claude Code skill?

Install via the ClaudSkills desktop app (one click) or copy SKILL.md from the source repository to ~/.claude/skills/lean-ctx/SKILL.md and restart Claude Code. Both flows are detailed at claudskills.com/install/.

What does the Lean Ctx skill do?

Is this skill free to install?

Yes. ClaudSkills is an open registry — every skill keeps its source repository's license, and manual install via copy is free. ClaudSkills Pro ($9/mo, $79/yr, or $149 one-time) adds one-click install via the desktop app and a multi-signal Quality Score.

When should I use the Lean Ctx skill?

Use Lean Ctx when your Claude Code task falls under the Product category — specifically in the product misc area. Claude Code auto-discovers installed skills and invokes the right one based on the task description, so you can also ask Claude directly (e.g. "use Lean Ctx" or describe the task and let Claude pick). Browse related skills at /category/product/.

What is a Claude Code skill and how does the Lean Ctx skill fit in?

A Claude Code skill is a SKILL.md file that lives under ~/.claude/skills/<name>/ and tells the Claude Code CLI agent how to perform a specific task (instructions, prompts, allowed tools). Skills are auto-discovered at session start. Lean Ctx is one of 67,000+ skills indexed in the open ClaudSkills catalog, classified under the Product category. Learn more at /learn/what-is-a-claude-skill/.

Attribution & license

Source: https://github.com/zaka33333-hash/claude-skills/blob/HEAD/lean-ctx/SKILL.md
Author: zaka33333-hash

Cite this skill

If you reference this skill in a blog post, paper, or documentation, you can cite it as:

APA

zaka33333-hash. (2026). Lean Ctx [Claude Code skill]. ClaudSkills. https://claudskills.com/skills/lean-ctx/

BibTeX

@misc{lean-ctx-2026,
  author    = {zaka33333-hash},
  title     = {Lean Ctx [Claude Code skill]},
  year      = {2026},
  publisher = {ClaudSkills},
  url       = {https://claudskills.com/skills/lean-ctx/}
}

Embed this skill

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Badge

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Part of ClaudSkills — the open registry for Claude Skills & Claude Code Skills. · What's New · Install guide · About · llms.txt

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