Developer & Agent Ecosystem

GST Maker Developer Documentation & MCP Server

Connect your business apps, ecommerce systems, or AI agents (Claude Desktop, Cursor, ChatGPT) directly with GST Maker's Indian GST invoicing and compliance engine.

OpenAPI 3.0 Spec

Machine-readable OpenAPI schema definition for all public and private endpoints.

openapi.json

Interactive API Docs

Test and inspect API endpoints live via Swagger UI.

Swagger Explorer

MCP Server (JSON-RPC)

Model Context Protocol server for Claude Desktop, Cursor, and agentic workflows.

MCP Endpoint

LLM Manifest

Standardized llms.txt protocol with agent instructions.

llms.txt

Model Context Protocol (MCP) Server Setup

Anthropic MCP 2024-11-05 Compliant

Connect GST Maker directly into Claude Desktop, Cursor IDE, or autonomous agent frameworks so AI models can validate Indian GSTINs, calculate CGST/SGST/IGST, search HSN codes, and draft invoices in real-time.

Option 1: Claude Desktop Integration (claude_desktop_config.json)

Add the following block to your Claude Desktop config file: 

{
  "mcpServers": {
    "gstmaker": {
      "command": "python",
      "args": ["-m", "core.mcp_server"],
      "cwd": "C:/Users/Aditya sharma/OneDrive/Desktop/saas-products/gst-maker-free"
    }
  }
}

Option 2: Cursor IDE Integration (.cursor/mcp.json) 

{
  "mcpServers": {
    "gstmaker": {
      "command": "python",
      "args": ["core/mcp_server.py"]
    }
  }
}

Option 3: Remote HTTP JSON-RPC (POST /mcp) 

curl -X POST https://gstmaker.com/mcp \
  -H "Content-Type: application/json" \
  -d '{
    "jsonrpc": "2.0",
    "id": 1,
    "method": "tools/call",
    "params": {
      "name": "calculate_gst",
      "arguments": {
        "taxable_amount": 25000,
        "gst_rate": 18,
        "is_interstate": false
      }
    }
  }'

Built-in MCP Tools List

Tool Name Input Arguments Action Description
lookup_hsn_code query: str Search Indian GST HSN/SAC codes, descriptions, and legal GST rates.
validate_gstin gstin: str Validates 15-digit GSTIN with Mod-36 checksum, state name, and PAN.
calculate_gst taxable_amount, gst_rate, is_interstate Computes exact CGST + SGST or IGST tax splits and final payable amount.
reverse_calculate_gst gross_amount, gst_rate Extracts base taxable amount and tax from a GST-inclusive gross total.
calculate_gstr_late_fee tax_liability, days_late, is_nil_return Computes Section 47 penalty and Section 50 interest on delayed GSTR filing.
generate_invoice_link hsn, rate, description, price Generates zero-login interactive guest invoice link ready for instant PDF download.
get_state_codes state_name (optional) Look up 2-digit Indian state GST jurisdiction codes (e.g. 07 Delhi, 27 Maharashtra).

Guest Pre-filled Invoicing Links (For AI Agents & Bots)

AI agents and external web apps can construct deep links to open the guest invoice generator with pre-filled line items, HSN/SAC codes, and GST rates:

https://gstmaker.com/try?hsn=847130&rate=18&desc=Laptops+and+Tablets

API Authentication

All private dashboard and business management endpoints utilize standard JWT Bearer token authentication. Include your token in the request header:

Authorization: Bearer YOUR_ACCESS_TOKEN