gtm

# Google Tag Manager

## Overview

This skill provides comprehensive expertise for Google Tag Manager (GTM), covering container setup, tag configuration, triggers, variables, data layer implementation, debugging, custom templates, and API automation. Whether you are implementing a new GTM setup, optimising an existing configuration, or troubleshooting issues, this skill has you covered.

## When to Use This Skill

Invoke this skill when:

- Setting up a new GTM container
- Configuring tags (GA4, Google Ads, Facebook Pixel, etc.)
- Creating triggers (page views, clicks, form submissions, etc.)
- Defining variables (data layer, custom JavaScript, constants, etc.)
- Implementing the data layer for e-commerce or custom events
- Debugging GTM issues using Preview mode or Tag Assistant
- Building custom templates with sandboxed JavaScript
- Automating GTM operations via the REST API
- Optimising container performance and organisation
- Ensuring privacy compliance and consent management

## Quick Start

### Container Setup

1. Create a GTM account at [tagmanager.google.com](https://tagmanager.google.com)
2. Create a container (Web, iOS, Android, or Server)
3. Install the container snippet on your website
4. Configure tags, triggers, and variables
5. Test in Preview mode
6. Publish

See [setup.md](references/setup.md) for detailed installation instructions.

### Basic Tag Configuration

```javascript
// Example: GA4 Configuration Tag
Tag Type: Google Analytics: GA4 Configuration
Measurement ID: G-XXXXXXXXXX
Trigger: All Pages
```

See [tags.md](references/tags.md) for comprehensive tag documentation.

### Data Layer Push

```javascript
// Push custom event to data layer
window.dataLayer = window.dataLayer || [];
dataLayer.push({
  'event': 'custom_event',
  'category': 'engagement',
  'action': 'button_click',
  'label': 'CTA Button'
});
```

See [datalayer.md](references/datalayer.md) for data layer patterns.

## Core Concepts

### Tags, Triggers, and Variables

**Tags** a