Getting it into your agent
It runs from inside its repository, so the clone comes first — what it calls does not travel with the file alone.
git clone --depth 1 https://github.com/mendixlabs/mxclinpx agentmods add skills/mendixlabs/mxcli/create-custom-widgetWrote 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.
[](https://agentmods.dev/skills/mendixlabs/mxcli/create-custom-widget)<a href="https://agentmods.dev/skills/mendixlabs/mxcli/create-custom-widget"><img src="https://agentmods.dev/badge/skills/mendixlabs/mxcli/create-custom-widget/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.
<a href="https://agentmods.dev/skills/mendixlabs/mxcli/create-custom-widget"><img src="https://agentmods.dev/badge/skills/mendixlabs/mxcli/create-custom-widget.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector warn
SkillSpector: 1 finding, up to high
These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →
- high Prompt Injection · line 116 Hidden instructions were detected in comments or invisible text. These could contain malicious directives. Manual review is recommended.Fix: Audit all comments and invisible characters. Remove any instructions that direct the agent to perform unauthorized actions. Use plain, reviewable content.
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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00050 | $0.03558 |
| Opus 5.5 | $0.00020 | $0.01423 |
| Sonnet 5.5 | $0.00010 | $0.00712 |
| Haiku 4.5 | $0.00005 | $0.00356 |
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 5d 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.
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 — 444 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Find it fast
sed -n '<from>,<to>p' SKILL.md one section rather than reading the file;
./mxcli syntax <topic> answers how do I write this for a fraction of either.
| lines | section |
|---|---|
| 31-35 | Prerequisites |
| 36-117 | Step 1: Scaffold the Project |
| 118-252 | Step 2: Define Widget Properties (widget.xml) |
| 253-313 | Step 3: Write the Entry Component |
| 314-339 | Step 4: Write the React Component |
| 340-368 | Step 5: Editor Config (optional but recommended) |
| 369-380 | Step 6: CSS Styles |
| 381-390 | Step 7: Build |
| 391-398 | Step 8: Install to Mendix Project |
| 399-422 | Common Widget Patterns |
| 423-435 | Checklist Before Build |
| 436-443 | Troubleshooting |
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"
}
}
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.
- 5d ago Changed · +21 lines 309c3b0e3031
- 1mo ago First seen · 423 lines · 50 tokens per session scan A be0a0b5fc2e3
create-custom-widget is a skill published in the GitHub repository mendixlabs/mxcli (131 stars, last pushed yesterday), licensed Apache-2.0. It adds 50 tokens to every session and 3,558 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 2026-08-30.
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