screen

screen is a skill for Claude Code, Codex from ibrahimmian36/leanscreen. It costs 0 tokens per session (894 once invoked), scanned A, original, no licence file.

A skill for checking whether informal mathematics and its Lean 4 theorem or definition statement faithfully match. Lean 4 is a language for expressing formal mathematics and proofs.

In plain words
What is it for?
Use it after drafting a statement, before committing a formalization, or when auditing benchmark files containing informal and Lean 4 pairs.
Why use it?
It helps find meaning-changing defects when formalizing, translating, editing, or reviewing mathematical statements.

Skill for Claude CodeCodex

Part of the leanscreen plugin — 1 skill, 1 MCP server shipped together

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.

agentmods
npx agentmods add skills/ibrahimmian36/leanscreen/screen
Any agent
npx skills add ibrahimmian36/leanscreen --skill screen
Clone the repo
git clone --depth 1 https://github.com/ibrahimmian36/leanscreen

Made for: Claude Code, Codex.

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

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 screen

README.md
[![agentmods](https://agentmods.dev/badge/skills/ibrahimmian36/leanscreen/screen.svg)](https://agentmods.dev/skills/ibrahimmian36/leanscreen/screen)
Your own site
<a href="https://agentmods.dev/skills/ibrahimmian36/leanscreen/screen"><img src="https://agentmods.dev/badge/skills/ibrahimmian36/leanscreen/screen.svg" alt="Measured on agentmods" height="20"></a>
Per session 0 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 894 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 1 finding. Scan, not verified.
Origin unknown 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 $0.00000 $0.00894
Opus 5 $0.00000 $0.00447
Sonnet 5 $0.00000 $0.00179
Haiku 4.5 $0.00000 $0.00089

Measured 4d ago against content hash 4ba69177e1c5, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

screen scanned grade A 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 4d 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.

Subtle steeringlowPrompt injection

Instructions that bias recommendations or shape behaviour without the user noticing.

Never tell the user a statement "is faithful," "is correct," or "passed

Downgraded: this mod is about security review, or the phrase is quoted, so it is likely naming the pattern rather than instructing it.

skills/screen/SKILL.md · 72 lines

The source is not reproduced here

A licence we could not identify

The repository carries a LICENSE file, but it is custom or dual enough that GitHub cannot name it and neither can this catalogue. Unknown terms are not permission, so the body is not copied here. Read the licence at the source and decide for yourself.

Read it on GitHub

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. 4d ago First seen · 72 lines · 0 tokens per session scan A 4ba69177e1c5

Subscribe to this mod's changes

screen is a skill published in the GitHub repository ibrahimmian36/leanscreen (6 stars, last pushed 16d ago), with no licence file. It costs nothing until one of its globs matches a file; then it loads 894 tokens. A static security scan graded it A with 1 finding (subtle steering). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

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