vertx-expert

vertx-expert is a skill for Claude Code, Codex from kinhluan/rules-quarkus-skills. It costs 37 tokens per session (785 once invoked), scanned A, original, MIT.

A specialist guide for Eclipse Vert.x, a Java toolkit for building event-driven and non-blocking applications, including systems used by Quarkus.

In plain words
What is it for?
Answering deep questions about Vert.x reactive programming, event loops, asynchronous code, messaging, database clients, and Vert.x integration with Quarkus.
Why use it?
It helps an agent avoid common mistakes such as blocking the event loop, the thread that handles asynchronous work.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one. Also seen: mentions Codex.

Good fit Answering deep questions about Vert.x reactive programming, event loops, asynchronous code, messaging, database clients, and Vert.x integration with Quarkus.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/kinhluan/rules-quarkus-skills/vertx-expert
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.

Any agent
npx skills add kinhluan/rules-quarkus-skills --skill vertx-expert
Clone the repo
git clone --depth 1 https://github.com/kinhluan/rules-quarkus-skills

Made for: Claude Code, Codex.

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 vertx-expert

README.md
[![agentmods](https://agentmods.dev/badge/skills/kinhluan/rules-quarkus-skills/vertx-expert/github.svg)](https://agentmods.dev/skills/kinhluan/rules-quarkus-skills/vertx-expert)
Your own site
<a href="https://agentmods.dev/skills/kinhluan/rules-quarkus-skills/vertx-expert"><img src="https://agentmods.dev/badge/skills/kinhluan/rules-quarkus-skills/vertx-expert/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.

agentmods 80×15 button for vertx-expert

Your own site · 80×15
<a href="https://agentmods.dev/skills/kinhluan/rules-quarkus-skills/vertx-expert"><img src="https://agentmods.dev/badge/skills/kinhluan/rules-quarkus-skills/vertx-expert.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 37 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 785 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin original 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 5.1 $0.00037 $0.00785
Opus 5 $0.00018 $0.00392
Sonnet 5 $0.00007 $0.00157
Haiku 4.5 $0.00004 $0.00078

Measured 11d ago against content hash f504214e79f4, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-11, from the pricing page.

Security

Grade A, and why

vertx-expert 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 11d 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.

.agent-skills/vertx-expert/SKILL.md · 66 lines

How it starts

The opening of the file, as written. The whole thing — 66 lines — stays where its author put it; the contents beside it link to each section on GitHub.

vertx-expert

Keyword: vertx | Platforms: gemini,claude,codex

Reactive Foundation Expert Skill - Specialized in the Eclipse Vert.x event-driven ecosystem.

Core Mandates

  • Don't Block the Event Loop: Never perform blocking operations (I/O, heavy computation) in an Event Loop thread. Use executeBlocking() if needed.
  • Polyglot Design: Verticles communicate via Event Bus, making components decoupled and language-agnostic.
  • Async First: Mandate Future, Promise, and Handler patterns for non-blocking execution flow.
  • Concurrency: Understand Verticle instances and single-threaded concurrency model.

Reactive Vert.x Components

  • Vert.x Web: Building high-performance, non-blocking HTTP APIs.
  • Event Bus: Distributed messaging system for horizontal scaling.
  • Reactive Clients: Using MySQL, PostgreSQL, Redis, and Kafka clients without blocking threads.
  • Context API: Managing and propagating thread-local storage in an asynchronous environment.

Vert.x + Quarkus Integration

  • Reactive Engine: Understanding how Quarkus uses Vert.x as its underlying I/O engine.
  • Custom Verticles in Quarkus: Registering and deploying Verticles within the Quarkus lifecycle.
  • Vert.x Mutiny: Leveraging SmallRye Mutiny (Uni, Multi) over standard Vert.x Futures.

Advanced Patterns

  • Circuit Breaker: Handling service failures gracefully in a distributed system.
  • Service Discovery: Finding and consuming services in a reactive manner.
  • Clustering: Using Hazelcast or Infinispan to cluster the Event Bus.

Expert Tips

  • Monitor the Event Loop using BlockedThreadChecker log warnings.
  • Prefer Vert.x Web Client over legacy RestTemplate or blocking clients.
  • Use Vertx.currentContext() for low-level async state management.

🌐 Reactive Knowledge Sources

Directive: If you encounter blocked thread warnings or need to implement complex event-driven flows, use web_fetch on these official guides.

Read the full file on GitHub · 66 lines

Files

What ships with it

1 file 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.

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. 11d ago First seen · 66 lines · 37 tokens per session scan A f504214e79f4

Subscribe to this mod's changes

vertx-expert is a skill published in the GitHub repository kinhluan/rules-quarkus-skills (3 stars, last pushed 3mo ago), licensed MIT. It adds 37 tokens to every session and 785 once invoked, about $0.0002 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 2026-08-31.