crear-extension

crear-extension is a skill for Claude Code from FacturaScripts/fs-claude-plugin. It costs 31 tokens per session (2,000 once invoked), scanned A, original, MIT.

A guide for creating FacturaScripts extensions, which add or change ERP features without editing the original plugin or core code. It covers extensions for models, controllers, and views.

In plain words
What is it for?
Use it to generate and structure extensions with fsmaker, including changes that run before or after a model is saved and changes to views.
Why use it?
It helps you customize FacturaScripts while keeping your changes separate from code that may later be updated.

Skill for Claude Code

Written for Claude Code: shipped in a Claude Code plugin.

Part of the fs-dev plugin — 28 skills, 11 agents, 3 hooks shipped together

Good fit Use it to generate and structure extensions with fsmaker, including changes that run before or after a model is saved and changes to views.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/facturascripts/fs-claude-plugin/crear-extension
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 FacturaScripts/fs-claude-plugin --skill crear-extension
Clone the repo
git clone --depth 1 https://github.com/FacturaScripts/fs-claude-plugin

Made for: Claude Code.

Or install fs-dev, the plugin that ships this one along with the rest of its 28 skills, 11 agents, 3 hooks.

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 crear-extension

README.md
[![agentmods](https://agentmods.dev/badge/skills/facturascripts/fs-claude-plugin/crear-extension.svg)](https://agentmods.dev/skills/facturascripts/fs-claude-plugin/crear-extension)
Your own site
<a href="https://agentmods.dev/skills/facturascripts/fs-claude-plugin/crear-extension"><img src="https://agentmods.dev/badge/skills/facturascripts/fs-claude-plugin/crear-extension.svg" alt="Measured on agentmods" height="20"></a>
Per session 31 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,000 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. Third-party audits
  • NVIDIA SkillSpector pass 7 Sept 2026
How audits are shown
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 $0.00031 $0.02000
Opus 5 $0.00015 $0.01000
Sonnet 5 $0.00006 $0.00400
Haiku 4.5 $0.00003 $0.00200

Measured 8d ago against content hash 3ede8d1ba175, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-08, from the pricing page.

Security

Grade A, and why

crear-extension 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 8d 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.

fs-dev/skills/crear-extension/SKILL.md · 257 lines

How it starts

The opening of the file, as written. The whole thing — 257 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Skill: Crear Extensión FacturaScripts

Las extensiones permiten añadir funcionalidad a clases del core o de otros plugins sin modificar su código fuente.

Atajo con fsmaker

Antes de crear los archivos a mano, considera usar la herramienta CLI:

fsmaker extension

fsmaker solicita el tipo de extensión (tabla, modelo, controlador, XMLView o vista Twig) y el nombre de la clase a extender, y genera el archivo base con la estructura correcta. Los apartados siguientes documentan la estructura completa para cuando necesites ajustar o completar la extensión manualmente.

Extensión de Modelo

Archivo: Plugins/MiPlugin/Extension/Model/NombreModelo.php

<?php

namespace FacturaScripts\Plugins\MiPlugin\Extension\Model;

use Closure;

class NombreModelo
{
    // Se ejecuta ANTES de guardar el modelo
    public function saveInsert(): Closure
    {
        return function () {
            // $this es el modelo original
            // Código a ejecutar antes de insertar
        };
    }

    // Se ejecuta DESPUÉS de guardar
    public function saveUpdate(): Closure
    {
        return function () {
            // Código a ejecutar después de actualizar
        };
    }

    // Se ejecuta al eliminar
    public function delete(): Closure
    {
        return function () {
            // Código a ejecutar al eliminar
        };
    }

    // Se ejecuta en test() (validación)
    public function test(): Closure
    {
        return function () {
            // Añadir validaciones extra
            // Retorna void, el pipe continúa
        };
    }
}

Métodos disponibles para extender en modelos

  • clear() — al instanciar el modelo, asigna valores predeterminados
  • delete() — tras el delete() del modelo
  • deleteBefore() — antes del delete(); si devuelve false, impide el borrado
  • save() — tras el save() del modelo
  • saveBefore() — antes del save(); si devuelve false, impide el guardado
  • saveInsert() — tras el saveInsert() del modelo
  • saveInsertBefore() — antes del saveInsert(); si devuelve false, lo impide
  • saveUpdate() — tras el saveUpdate() del modelo
  • saveUpdateBefore() — antes del saveUpdate(); si devuelve false, lo impide
  • test() — tras el test() del modelo
  • testBefore() — antes del test(); si devuelve false, lo impide
  • url() — tras el url() del modelo
  • onChange() — antes del saveUpdate(), para detectar cambios en columnas

Read the full file on GitHub · 257 lines

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. 8d ago First seen · 257 lines · 31 tokens per session scan A 3ede8d1ba175

Subscribe to this mod's changes

crear-extension is a skill published in the GitHub repository FacturaScripts/fs-claude-plugin (8 stars, last pushed 5d ago), licensed MIT. It adds 31 tokens to every session and 2,000 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.

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