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 skills add mendixlabs/mxcli --skill java-actionsgit clone --depth 1 https://github.com/mendixlabs/mxcliWrote 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/java-actions)<a href="https://agentmods.dev/skills/mendixlabs/mxcli/java-actions"><img src="https://agentmods.dev/badge/skills/mendixlabs/mxcli/java-actions/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/java-actions"><img src="https://agentmods.dev/badge/skills/mendixlabs/mxcli/java-actions.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector pass
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 | $0.00052 | $0.04987 |
| Opus 5.5 | $0.00021 | $0.01995 |
| Sonnet 5.5 | $0.00010 | $0.00997 |
| Haiku 4.5 | $0.00005 | $0.00499 |
Grade A, and why
java-actions 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 — 642 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 |
|---|---|
| 28-39 | Reference files |
| 40-48 | When to Use This Skill |
| 49-55 | Overview |
| 56-332 | Part 2.5: Creating Java Actions in MDL |
| 333-526 | Part 3: Calling Java Actions from MDL |
| 527-540 | Validation Checklist |
| 541-551 | Common Errors |
| 552-559 | Related Documentation |
| 560-641 | Quick Reference |
Mendix Java Actions Skill
This skill provides comprehensive guidance for creating and using custom Java actions in Mendix projects.
Reference files
SKILL.md covers declaring a Java action in MDL and calling it from a microflow —
the parts that touch the model. The Java side is next door:
reference/writing-java.md— creating the action in Studio Pro, writing theexecuteActionbody, the Core API surface you have, and the recurring patterns (HTTP calls, file handling, batch work).reference/best-practices.md— error handling, transactions and rollback, logging, threading, security, and performance. Read it before shipping a Java action that touches data or an external system.
When to Use This Skill
Use this skill when:
- You need to extend Mendix with custom Java logic
- Building integrations with external Java libraries
- Implementing complex algorithms not feasible in microflows
- Calling Java actions from MDL microflows
- Debugging Java action calls
Overview
Java actions allow you to extend Mendix with custom Java code. The workflow is:
- Define the Java action in Studio Pro (parameters, return type)
- Implement the Java code in Eclipse/IDE
- Call the Java action from microflows using MDL
Part 2.5: Creating Java Actions in MDL
MDL supports defining Java actions with inline Java code using create java action.
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.
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 Changed · +2 lines 15f25a67b175
- 4d ago Changed · +18 lines 8b4268682a8e
- 12d ago Changed · +7 lines ec8137d31961
- 14d ago Changed · +18 lines 5d29d607969d
- 15d ago Changed · +5 lines ecf883cf2a68
- 19d ago Changed · +5 lines e2ccf5c3940f
- 1mo ago First seen · 587 lines · 52 tokens per session scan A b783e0810cb4
java-actions is a skill published in the GitHub repository mendixlabs/mxcli (130 stars, last pushed yesterday), licensed Apache-2.0. It adds 52 tokens to every session and 4,987 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.
Other skills, from other repositories
react-component-design
Designs or reviews React component APIs. Handles prop drilling decisions, composition patterns, controlled/uncontrolled contracts, and minimal public API surfaces for React 18+ TypeScript components. Invoked when creating new components, refactoring existing ones, or reviewing component contracts.
tinystruct-patterns
Expert guidance for developing with the tinystruct Java framework. Use when working on the tinystruct codebase or any project built on tinystruct — including creating Application classes, @Action-mapped routes, unit tests, ActionRegistry, HTTP/CLI dual-mode handling, the built-in HTTP server, the event system, JSON…
springboot-patterns
Spring Boot architecture patterns, REST API design, layered services, data access, caching, async processing, and logging. Use for Java Spring Boot backend work.
sinch-sdks
Sinch SDK installation and client initialization for Node.js, Python, Java, and .NET. Use when installing a Sinch SDK, initializing SinchClient, setting up SDK credentials, configuring conversation region in SDK, or building a multi-product SDK client. For In-App Calling SDKs, see sinch-in-app-calling.
springboot-patterns
Spring Boot architecture patterns, REST API design, layered services, data access, caching, async processing, and logging. Use for Java Spring Boot backend work.
quarkus-patterns
Quarkus 3.x LTS architecture patterns with Camel for messaging, RESTful API design, CDI services, data access with Panache, and async processing. Use for Java Quarkus backend work with event-driven architectures.