GST Pro MCP Server

Model Context Protocol server for GST Pro that enables AI assistants like Claude Desktop and Claude CLI to interact with your Shopify GST invoice templates.

Features

• List & Read Templates - Browse and read all your GST Pro templates
• Edit Templates - Modify Liquid templates, GraphQL queries, and configurations
• Validation - Validate Liquid syntax and GraphQL queries before deploying
• AI-Powered - Get intelligent suggestions and modifications from AI assistants
• Secure - API key authentication tied to your GST Pro shop

Installation

Global Installation

npm install -g @helloastral/gst-pro-mcp-server

Local Installation

npm install @helloastral/gst-pro-mcp-server

Setup

1. Get Your API Key

1. Log into your GST Pro app inside Shopify admin
2. Go to Settings -> Integrations
3. Find the "MCP" section and generate an API key

2. Configure Your AI Assistant

Claude Desktop

Add to your claude_desktop_config.json:

{
  "mcpServers": {
    "gst-pro": {
      "command": "npx",
      "args": ["-y", "@helloastral/gst-pro-mcp-server"],
      "env": {
        "GST_PRO_API_KEY": "your_api_key_here",
        "GST_PRO_APP_URL": "https://api.gstpro.helloastral.com"
      }
    }
  }
}

Claude CLI

claude mcp add --transport stdio gst-pro --env GST_PRO_API_KEY=your_api_key_here --env GST_PRO_APP_URL=https://api.gstpro.helloastral.com -- npx -y @helloastral/gst-pro-mcp-server

Environment Variables

| Variable | Required | Default | Description | | ----------------- | -------- | ----------------------- | ------------------------ | | GST_PRO_API_KEY | Yes | - | Your GST Pro MCP API key | | GST_PRO_APP_URL | No | http://localhost:4321 | GST Pro API URL | | GST_PRO_DEBUG | No | false | Enable debug logging |

Available Tools

list_templates

List all V2 templates in your shop.

get_template

Get metadata of a specific template by ID.

Arguments:

• templateId (string) - The template ID

read_file

Read a specific file from a template. Falls back to the base template's content if the shop has not customised it yet.

Arguments:

• templateId (string) - The template ID
• path (string) - File path: template.liquid, query.graphql, schema.json, or config.json

write_file

Write or update a file in a template. Promotes the shop template to a customised state on first edit.

Arguments:

• templateId (string) - The template ID
• path (string) - File path: template.liquid, query.graphql, schema.json, or config.json
• content (string) - The file content

validate_liquid

Validate Liquid template syntax.

Arguments:

• liquid (string) - The Liquid template code

validate_query

Validate GraphQL query against the Shopify schema.

Arguments:

• query (string) - The GraphQL query
• type (string) - Document type: INVOICE, PACKING, DRAFT, or REFUND

Usage Examples

After setup, you can ask Claude:

"List all my GST Pro templates"

"Show me the invoice template and add a payment terms section"

"Validate the GraphQL query in my packing slip template"

Context Prompt

Access comprehensive context about working with GST Pro templates:

/gst-pro-context

Template Structure

GST Pro templates consist of four files:

1. template.liquid - HTML/CSS document template using Liquid syntax
2. query.graphql - GraphQL queries to fetch Shopify order data
3. schema.json - JSON schema defining customizable fields
4. config.json - Template configuration and settings

Support

• Website: helloastral.com
• Documentation: Available in the GST Pro app
• Issues: Contact support through the GST Pro app

License

MIT (c) Astral Commerce