shell-guard by youllook: Claude Code mod code and design

What it does

Draws toasts
Watches Bash, PowerShell calls and can refuse them

Good points

No network calls
Starts no processes
Small: 160 lines
Written in TypeScript

Code to start from

Two kinds: a starter modscode writes from the design above, and the lines of the mod's own code that draw it.

Starter (register.tsx)

import type { Register } from 'claude-code'

// Drawn like shell-guard by youllook (toast), as modscode read it from the mod's code:
// https://modscode.com/gallery/youllook-shell-guard/
// Written by modscode from that reading, not copied from the mod: use it as you like.
// Each value below stands for one the mod works out at run time; put in your own.
export const register: Register = on => {
  on('session.start', async ($, e, next) => {
    await $.ui.toast(`🛡 shell-guard 擋下一個會出錯的 Bash 指令`)
    await $.ui.toast(`🔧 shell-guard：Windows 路徑反斜線已轉正斜線`)
    return next(e)
  })
}

The mod's own code

Its licence text was not found at the commit read, so only the places in the source are linked.

youllook/ClaudeMods

What its code calls

tool calls

The design, read from code

Claude — Code

🛡 shell-guard 擋下一個會出錯的 Bash 指令

🔧 shell-guard：Windows 路徑反斜線已轉正斜線

Ask Claude…

Drawn from the mod's source at the commit read, not from a run: a list is drawn three times, a condition takes its first branch that draws in the desktop app, and a value only the run time knows is shown as a made-up sample (dotted underline) or left out. Colours and type are this site's.

What its code shows

Read from the source at commit b1f126cd62a9 on 2026-10-06. The first group decides whether a mod is listed; the rest is for you to weigh. A later commit is not read until the next crawl.

Decides the listing: code you can check
Entry read	Every module hooks/hooks.json names was read.plugins/shell-guard/hooks/register.ts
Parses	Every file parses as TypeScript or JavaScript.1 files parsed
All its code is in the mod	Every import is a file of the mod or the engine's own module; no packages, no require.all its code is in the mod
Readable	No minified lines, no eval or new Function, no import of a computed path, no encoded blobs.no minified code, no eval, no encoded blobs
Calls in the open	Network and programs are reached as $.http.fetch and $.process.run in place, never passed around.every call outside goes through $ in the open
For you to weigh before installing
Where it draws	The terminal, the desktop app, both, or nothing (hooks only: a guard or a prompt rewriter), as its code says. Shown, never a reason to leave a mod out.draws in the terminal and the desktop app, the same in both
Install line	Whether its repository's own .claude-plugin/marketplace.json lists it, so it installs from that marketplace with the lines on its page.listed in its repository's .claude-plugin/marketplace.json: installs from there
Programs on Windows	Whether every program it starts through $.process exists on Windows (tail, date, open, osascript, /usr/… do not).runs no program a Windows PC lacks
Network	Whether every fetch names its https host in the code.no network
Programs	Whether every program it starts is named in the code and is not a shell, an interpreter or a network tool.starts no programs
Reads and sends	Whether it both reads files or environment variables and reaches the network.reaches no network
Keys in the source	Whether the source holds what looks like an API key or a private key.no keys in the source
Licence	An open licence (MIT, Apache-2.0, BSD, ISC, Unlicense, 0BSD, CC0) with its text lets modscode show its code; otherwise the code is linked.MIT

This is a reading of the code text, not a security review: it does not run the mod, and it cannot see what a program the mod starts does. The check before installing is yours. How mods are chosen

Install it

Check it yourself before you install it. Mods run unsandboxed, with your permissions, and modscode does not vouch for what this code does. Read the code below (or run claude plugin validate . in its folder), weigh what it reaches, and install the commit you read.

Its repository is its marketplace. Add that marketplace (in the terminal with these commands, or in the desktop app's plugin settings) and install the mod from it:

/plugin marketplace add youllook/ClaudeMods

/plugin install shell-guard@claude-mods

This installs the marketplace's latest commit, which may not be the one read here (b1f126cd62a9). Compare them before you install.

Ask Claude about it

With the modscode connector added, Claude can read this design, what its code reaches and its code, and build on them. Ask it like this:

Read the modscode design "youllook-shell-guard" with its code and make me a pane like it

Search them from Claude: the MCP connector