Agent Skills: WordPress Development Skill

WordPress Development Skill

Atomic skill for mastering WordPress theme and plugin development

Overview

Comprehensive skill for building WordPress themes, plugins, and Gutenberg blocks. Covers WordPress 6.x with focus on modern development practices and security.

Skill Parameters

Input Validation

interface SkillParams {
  topic:
    | "themes"           // Classic, block, FSE
    | "plugins"          // Architecture, hooks, settings
    | "gutenberg"        // Blocks, patterns, InnerBlocks
    | "rest-api"         // Custom endpoints, authentication
    | "security"         // Nonces, sanitization, escaping
    | "woocommerce";     // Store extensions

  level: "beginner" | "intermediate" | "advanced";
  wp_version?: "6.4" | "6.5" | "6.6" | "6.7";
  theme_type?: "classic" | "block" | "hybrid";
}

Validation Rules

validation:
  topic:
    required: true
    allowed: [themes, plugins, gutenberg, rest-api, security, woocommerce]
  level:
    required: true
  wp_version:
    default: "6.6"

Learning Modules

Module 1: Theme Development

beginner:
  - Theme structure and files
  - Template hierarchy
  - Enqueuing styles/scripts

intermediate:
  - Custom post types
  - Theme customizer
  - Block theme basics

advanced:
  - Full Site Editing
  - theme.json deep dive
  - Performance optimization

Module 2: Plugin Development

beginner:
  - Plugin structure
  - Actions and filters
  - Shortcodes

intermediate:
  - Settings API
  - Custom database tables
  - AJAX handling

advanced:
  - Plugin architecture patterns
  - WP-CLI commands
  - Multisite support

Module 3: Gutenberg Blocks

beginner:
  - Block basics and block.json
  - Edit and save functions
  - Block attributes

intermediate:
  - InnerBlocks
  - Block variations
  - Server-side rendering

advanced:
  - Interactivity API
  - Block Bindings
  - Custom block categories

Error Handling & Retry Logic

errors:
  HOOK_ERROR:
    code: "WP_001"
    recovery: "Check hook name and timing"

  SECURITY_ERROR:
    code: "WP_002"
    recovery: "Add proper escaping/sanitization"

retry:
  max_attempts: 3
  backoff:
    type: exponential
    initial_delay_ms: 100

Code Examples

Plugin Header

<?php
/**
 * Plugin Name: My Custom Plugin
 * Description: A custom WordPress plugin
 * Version: 1.0.0
 * Requires PHP: 8.0
 * Author: Developer
 */

declare(strict_types=1);

defined('ABSPATH') || exit;

final class MyCustomPlugin
{
    public function __construct()
    {
        add_action('init', [$this, 'registerPostType']);
        add_action('rest_api_init', [$this, 'registerRoutes']);
    }

    public function registerPostType(): void
    {
        register_post_type('portfolio', [
            'labels' => ['name' => __('Portfolio')],
            'public' => true,
            'show_in_rest' => true,
            'supports' => ['title', 'editor', 'thumbnail'],
        ]);
    }

    public function registerRoutes(): void
    {
        register_rest_route('myplugin/v1', '/items', [
            'methods' => 'GET',
            'callback' => [$this, 'getItems'],
            'permission_callback' => '__return_true',
        ]);
    }

    public function getItems(\WP_REST_Request $request): \WP_REST_Response
    {
        $items = get_posts(['post_type' => 'portfolio']);
        return new \WP_REST_Response($items, 200);
    }
}

new MyCustomPlugin();

Gutenberg Block (block.json)

{
  "$schema": "https://schemas.wp.org/trunk/block.json",
  "apiVersion": 3,
  "name": "myplugin/testimonial",
  "title": "Testimonial",
  "category": "widgets",
  "icon": "format-quote",
  "description": "Display a testimonial",
  "supports": {
    "html": false,
    "align": ["wide", "full"]
  },
  "attributes": {
    "content": { "type": "string" },
    "author": { "type": "string" }
  },
  "textdomain": "myplugin",
  "editorScript": "file:./index.js",
  "style": "file:./style-index.css"
}

Security Best Practices

<?php
// Input sanitization
$title = sanitize_text_field($_POST['title'] ?? '');
$content = wp_kses_post($_POST['content'] ?? '');
$id = absint($_POST['id'] ?? 0);

// Output escaping
echo esc_html($title);
echo esc_attr($attribute);
echo esc_url($url);
echo wp_kses_post($content);

// Nonce verification
if (!wp_verify_nonce($_POST['_wpnonce'], 'my_action')) {
    wp_die('Security check failed');
}

// Capability check
if (!current_user_can('edit_posts')) {
    wp_die('Unauthorized');
}

// Database queries
global $wpdb;
$results = $wpdb->get_results(
    $wpdb->prepare(
        "SELECT * FROM {$wpdb->prefix}custom_table WHERE id = %d",
        $id
    )
);

Troubleshooting

| Problem | Solution | |---------|----------| | Hook not firing | Check hook name spelling and timing | | Block not appearing | Verify block.json, run npm build | | REST API 403 | Check permission_callback | | White screen | Enable WP_DEBUG, check error.log |

Debug Constants

// wp-config.php
define('WP_DEBUG', true);
define('WP_DEBUG_LOG', true);
define('WP_DEBUG_DISPLAY', false);
define('SCRIPT_DEBUG', true);

Quality Metrics

| Metric | Target | |--------|--------| | Security compliance | 100% | | Hook correctness | 100% | | WPCS compliance | 100% |

Usage

Skill("php-wordpress", {topic: "gutenberg", level: "intermediate"})