slim

slim is a skill for Claude Code from mirkobozzetto/arsenal. It costs 54 tokens per session (884 once invoked), scanned A, original, MIT.

A tool for reducing the instructions Claude Code loads in every session without removing rules. It measures files, sorts guidance into always-loaded rules, skills, or path-specific rules, shows the changes, and writes only after approval.

In plain words
What is it for?
Use it to examine CLAUDE.md files and imported rules, move procedures into skills, attach rules to matching paths, and compare instruction size before and after.
Why use it?
Keeping every instruction loaded all the time uses context even when a rule is irrelevant. This separates general guidance from procedures and file-specific guidance while checking that rules remain accounted for.

Skill for Claude Code

Written for Claude Code: argument-hint in frontmatter. Also seen: mentions CLAUDE.md; mentions Claude Code.

Part of the slim plugin — 1 skill shipped together

Good fit Use it to examine CLAUDE.md files and imported rules, move procedures into skills, attach rules to matching paths, and compare instruction size before and after.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/mirkobozzetto/arsenal/slim
Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent
npx skills add mirkobozzetto/arsenal --skill slim
Clone the repo
git clone --depth 1 https://github.com/mirkobozzetto/arsenal

Made for: Claude Code.

Or install slim, the plugin that ships this one along with the rest of its 1 skill.

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 slim

README.md
[![agentmods](https://agentmods.dev/badge/skills/mirkobozzetto/arsenal/slim/github.svg)](https://agentmods.dev/skills/mirkobozzetto/arsenal/slim)
Your own site
<a href="https://agentmods.dev/skills/mirkobozzetto/arsenal/slim"><img src="https://agentmods.dev/badge/skills/mirkobozzetto/arsenal/slim/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 slim

Your own site · 80×15
<a href="https://agentmods.dev/skills/mirkobozzetto/arsenal/slim"><img src="https://agentmods.dev/badge/skills/mirkobozzetto/arsenal/slim.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 54 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 884 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 original No closer match found 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 $0.00054 $0.00884
Opus 5.5 $0.00022 $0.00354
Sonnet 5.5 $0.00011 $0.00177
Haiku 4.5 $0.00005 $0.00088

Measured 2d ago against content hash 2281d9e2c436, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

slim 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 2d ago.

The scan reads SKILL.md. This mod also ships 2 executable files (scripts/check.cjs, scripts/weigh.cjs), listed below but not scanned — reading those needs a real analyzer, not pattern matching.

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.

plugins/slim/skills/slim/SKILL.md · 57 lines

What it actually says

Slim

Lighten what every session pays before its first word, and lose no rule. Resolve scripts/ from this skill's directory. Run each script with Bash run_in_background: true and read its output when it ends: a foreground Bash may run in another shell, without the session's CLAUDE_CONFIG_DIR or working directory. <work> is a new scratch folder for this run. Talk in the conversation language.

  1. Weigh. node scripts/weigh.cjs --save <work>/before.json. Show its table: every file loaded at launch, its size and its share. An argument narrows the files to slim; the weighing stays whole.
  2. Sort. Read each file and give every block one destination:
    • stays loaded: a rule every session needs, kept short;
    • skill: a procedure, or a block for one kind of task. It becomes skills/<name>/SKILL.md in the same scope (<config>/skills/ or <project>/.claude/skills/), its description saying when it applies;
    • paths: rule: a block that matters only for matching files. It loads after a matching Read, Write or Edit, and user-level patterns start from the session's working directory: a rule needed before any read stays loaded;
    • evidence: a dated citation, a date, the story of why. It moves word for word to evidence/<file>.md beside rules/ (<config>/evidence/ or <project>/.claude/evidence/), never inside rules/, where every .md loads. List the duplicates and contradictions between files too, each with both passages. Never edit MEMORY.md, nor a block a tool generates (the GitNexus block between its markers): weigh and report them only.
  3. Show. File by file: what moves where, and each rewritten or removed sentence beside its original. Write nothing yet. Ask one question for the go; the user may validate some files and not others.
  4. Save. node scripts/check.cjs save <work> <files to change>. Exit 2 names a file with changes not committed: stop there.
  5. Write only what was validated. Move text word for word. Each validated rewrite or removal goes in <work>/rewrites.json as {"from": "<original>", "to": "<new, or empty>"}. Add once, to the CLAUDE.md of that scope, one line saying where its evidence lives.
  6. Verify. node scripts/check.cjs verify <work> --in <evidence dir> --in <rules dir> --in <each new skill or rule> --rewrites <work>/rewrites.json. It puts back, as it was, any file with a piece found nowhere: report each lost piece in one line, and never write that file again another way.
  7. Commit each changed file in the repository that holds it: one commit per file, with the evidence, skill or rule it fed, chore(rules): slim <file>. git revert undoes it. A file outside Git keeps its .slim.bak copy.
  8. Weigh again. node scripts/weigh.cjs --compare <work>/before.json. Show before, after and the gain. Counts are estimates; /context in a fresh session gives the exact one. For stale references, suggest /doctor prompt-audit (Claude Code 2.1.283 or later) in one line.
Files

What ships with it

2 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

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. 2d ago First seen · 57 lines · 54 tokens per session scan A 2281d9e2c436

Subscribe to this mod's changes

slim is a skill published in the GitHub repository mirkobozzetto/arsenal (23 stars, last pushed 3d ago), licensed MIT. It adds 54 tokens to every session and 884 once invoked, about $0.0002 per session on Opus 5.5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-11-04.

Related

slim compared with skills from other repositories

slim next to 6 skills from other repositories
ModTypeStarsLast pushLicenceScanTokensWorks with
slimmirkobozzetto/arsenalSkill233d agoMITA54Claude Code
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switch-clientssuboss87/FDEOpsSkill85717d agoMITA32Claude Code, Codex
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Changelog CuratorNotysoty/openagentskillsSkill92mo agoMITA26Claude Code, Codex
PR Description WriterNotysoty/openagentskillsSkill92mo agoMITA19Claude Code, Codex
Release Notes GeneratorNotysoty/openagentskillsSkill92mo agoMITA22Claude Code, Codex