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.
npx agentmods add skills/mendixlabs/mxcli/create-custom-widgetnpx skills add mendixlabs/mxcli --skill create-custom-widgetgit clone --depth 1 https://github.com/mendixlabs/mxcliWhat 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 | $0.00050 | $0.03314 |
| Opus 5 | $0.00025 | $0.01657 |
| Sonnet 5 | $0.00010 | $0.00663 |
| Haiku 4.5 | $0.00005 | $0.00331 |
Grade A, and why
create-custom-widget 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 yesterday.
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.
How it starts
The opening of the file, as written. The whole thing — 423 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Create Custom Pluggable Widget
Build a Mendix pluggable widget from scratch using React + TypeScript. Produces a .mpk file ready for Studio Pro.
Prerequisites
- Node.js >= 16
- npm
Step 1: Scaffold the Project
Create a directory and generate all source files. Use PascalCase for the widget name.
mkdir -p <WidgetName>/src/components <WidgetName>/src/ui
package.json
{
"name": "<widget-name>",
"widgetName": "<WidgetName>",
"version": "1.0.0",
"description": "<description>",
"license": "Apache-2.0",
"config": {
"projectPath": "./tests/testProject",
"mendixHost": "http://localhost:8080",
"developmentPort": 3000
},
"packagePath": "com.example.widgets",
"scripts": {
"dev": "pluggable-widgets-tools start:web",
"build": "pluggable-widgets-tools build:web",
"lint": "pluggable-widgets-tools lint",
"lint:fix": "pluggable-widgets-tools lint:fix"
},
"devDependencies": {
"@mendix/pluggable-widgets-tools": "^11.6.0",
"@types/big.js": "^6.0.2"
},
"dependencies": {
"classnames": "^2.2.6"
},
"resolutions": {
"react": "^19.0.0",
"react-dom": "^19.0.0",
"@types/react": "^19.0.0",
"@types/react-dom": "^19.0.0"
},
"overrides": {
"react": "^19.0.0",
"react-dom": "^19.0.0",
"@types/react": "^19.0.0",
"@types/react-dom": "^19.0.0"
}
}
Naming rules:
name: kebab-case (npm package name)widgetName: PascalCase (matches .xml and .tsx filename)packagePath: reverse domain, dot-separated (e.g.com.example.widgets)
tsconfig.json
{
"extends": "./node_modules/@mendix/pluggable-widgets-tools/configs/tsconfig.base.json"
}
src/package.xml
<?xml version="1.0" encoding="utf-8" ?>
<package xmlns="http://www.mendix.com/package/1.0/">
<clientModule name="<WidgetName>" version="1.0.0" xmlns="http://www.mendix.com/clientModule/1.0/">
<widgetFiles>
<widgetFile path="<WidgetName>.xml"/>
</widgetFiles>
<files>
<file path="com/example/widgets/<widgetname>"/>
</files>
</clientModule>
</package>
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.
- yesterday First seen · 423 lines · 50 tokens per session scan A be0a0b5fc2e3
create-custom-widget is a skill published in the GitHub repository mendixlabs/mxcli (115 stars, last pushed 2d ago), licensed Apache-2.0. It adds 50 tokens to every session and 3,314 once invoked, about $0.0003 per session on Opus 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 2026-08-30.
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