1. Problem Statement

GST compliance and litigation has become increasingly complex, with frequent notices being issued to taxpayers on issues like ITC mismatches, late filings, classification disputes, and procedural lapses.

For Chartered Accountants and professionals, the biggest challenge is not just interpreting the law but drafting structured, legally sound, and submission-ready replies.

Existing GPTs, including the ICAI CA GST GPT, provide broad knowledge and summaries of law. However, professionals face the following limitations when using generic GPTs:

1. Hallucination: Creation of non-existent references and irrelevant case laws.
2. Irrelevance: Answers often verbose and not tailored to the specific issue of the notice.
3. Lack of Drafting Format: No consistent professional format acceptable to tax authorities.
4. Overloaded Case Law Citations: Long lists of judgments, many of which are not directly applicable.
5. Compliance Risk: Not safe to directly rely on outputs for legal submissions.

This highlighted the need for a specialized, controlled, and professional drafting assistant tailored for GST practitioners.

2. Development of Custom GST GPT – GST Guide

The Custom GST GPT was designed as a practical tool for Chartered Accountants. Its development included:

1. Structured JSON Prompts
2. Ensured that every reply follows a defined legal draft format:
3. Addressing
4. Facts of the case
5. Grounds of defence with law & case reference
6. Prayer/relief sought
7. This guarantees consistency and professionalism in every reply.
8. SOP for Draft Replies
9. A Standard Operating Procedure was embedded so that replies are uniform and submission-ready.
10. Steps: Proper addressing → Statement of facts → Legal grounds (sections/rules) → Only relevant judgments → Prayer.
11. Curated Knowledge Base
12. Based on Acts, Rules, Notifications, Circulars, and only selected landmark judgments.
13. Avoids unnecessary or irrelevant citations.
14. Two Modes of Response
15. Law Referencer Mode: Answers queries strictly based on law as on date.
16. Drafting Mode for Notices: Drafts replies using law applicable for the notice period, ensuring contextual accuracy.
17. Continuous Testing
18. Validated against actual GST notices (ITC mismatch, classification disputes, etc.) to refine accuracy and usability.

3. Uses of the Custom GST GPT

1. Drafting Replies to GST Notices
2. Creates submission-ready replies in legal draft format.
3. Saves professional time and ensures accuracy.
4. GST Law Referencer
5. Provides answers strictly as per current law provisions.
6. Reliable for day-to-day legal interpretation.
7. GST Rate Finder
8. Provides GST rates for goods and services.
9. Shows both current and historical rates.
10. Updated with recent changes, including those effective from 22nd September 2025.

4. How It is Different from Other Generic GPTs (e.g., ICAI CA GST GPT)

5. Conclusion – Utility for Professionals

The Custom GST GPT – GST Guide – is not just another knowledge tool but a professional drafting assistant.

For professionals, it:

1. Reduces time and effort in drafting replies to notices.
2. Minimizes risk by avoiding hallucinations and irrelevant case laws.
3. Provides accurate legal interpretation as on date for research.
4. Simplifies compliance by giving GST rates, both historical and current.

In essence, it bridges the gap between AI technology and real-world GST practice, offering Chartered Accountants a low-risk, reliable, and practical assistant for litigation and compliance.

Link to the Custom GST GPT

👉 https://chatgpt.com/g/g-68a85ee297e4819190f01c696a7a346c-gst-guide-by-mohit-gaba