Freelancer / small business (India)

GST invoice drafter

Immediate result: A GST invoice layout with all required fields and correctly split CGST/SGST or IGST.

Problem it solvesFreelancers and small businesses make GST invoice mistakes that cause compliance problems.

Add this skill to

You paste

Delhi freelancer → Delhi client · design services SAC 998391 · ₹50,000 · 18%

You get

Intra-state (Delhi → Delhi): CGST 9% = ₹4,500 + SGST 9% = ₹4,500

Total: ₹59,000 (Rupees fifty-nine thousand only)

Check: invoice number is sequential for the financial year.

About this skill

About GST invoice drafter

Freelancers and small businesses in India often make GST invoice mistakes that cause trouble at filing time. This skill lays out an invoice with the required fields, decides between CGST plus SGST and IGST from the supplier and buyer states, calculates tax and totals with the working shown, and adds the amount in words. For exports under a Letter of Undertaking it notes zero-rating instead of charging IGST. Confirm rates and SAC codes with your chartered accountant before sending. To use it, paste the skill into your assistant and send your details and GSTIN, client details and state, services or goods with SAC/HSN, amounts and date; the reply opens with “Invoice”.

GST invoice drafter AI skill for Freelancer / small business (India): you paste "Delhi freelancer → Delhi client · design services SAC 998391 · ₹50,000 · 18%" and get "Intra-state (Delhi → Delhi): CGST 9% = ₹4,500 + SGST 9% = ₹4,500"
GST invoice drafter — example input and the first lines it returns. Works in ChatGPT, Claude and Gemini.
Job profile
Founders & small business · Freelancer / small business (India)
Works in
ChatGPT, Claude, Gemini, Copilot, Claude Code
Format
Agent Skills (SKILL.md)
Price
Free, no sign-up
Install instructions

Copy, paste, send

  1. Cold email writerCopy skillCopied ✓1 Copy the skillPress Copy skill.
  2. ANY AI ASSISTANTSKILLPaste here, then press Enter2 Paste it into a new chatChatGPT, Claude, Gemini or Copilot.
  3. ANY AI ASSISTANT3 Send your inputSend your details and GSTIN.
The skill — paste this into your AI assistant
# Skill: GST invoice drafter

You are running the "GST invoice drafter" skill for me. I work as: Freelancer / small business (India). What I need from you: a GST invoice layout with all required fields and correctly split CGST/SGST or IGST.

## When I send you my details and GSTIN, client details and state, services or goods with SAC/HSN, amounts and date
1. Lay out required invoice fields.
2. Work out intra-state (CGST + SGST) or inter-state (IGST) from the states given.
3. Calculate tax and totals, showing the maths.
4. Add the amount in words and declarations.

## Reply in this format
- Invoice (table layout)
- Tax calculation
- Fields to check

## Rules
- This prepares an invoice; confirm rates and SAC codes with your CA.
- Export of services: note LUT and zero-rating rather than charging IGST if the user says they have an LUT.
- Use only the facts I give you; mark anything you had to assume with [ASSUMPTION].
- If something essential is missing, ask me one short question, then continue.
- No preamble or filler: start with the result.

Confirm you're ready in one line, then wait for me to send my details and GSTIN, client details and state, services or goods with SAC/HSN, amounts and date.

Then sendYour details and GSTIN, client details and state, services or goods with SAC/HSN, amounts and date. For example: Delhi freelancer → Delhi client · design services SAC 998391 · ₹50,000 · 18%

ChatGPT

  1. Fastest: paste the skill as your first message in a new chat, then send your input.
  2. To keep it: open a Project, choose Instructions (or Settings → Personalization → Custom instructions for every chat) and paste it there.
  3. To share it with a team: create a custom GPT and paste the skill into its Instructions.
  4. In the Codex app: copy the skill's folder into ~/.codex/skills/ (or Customize → Skills → Add → Create skill).

Claude

  1. Fastest: paste the skill as your first message in a new chat, then send your input.
  2. To keep it: create a Project, open Project instructions and paste the skill.
  3. As a Claude Skill: download the skill's ZIP, then in Claude open Settings → Skills → Add → Upload skill and choose the file.

Gemini

  1. Fastest: paste the skill as your first message in a new chat, then send your input.
  2. To keep it: open Gems → New Gem, paste the skill into Instructions and save.

Microsoft Copilot

  1. Fastest: paste the skill as your first message, then send your input.
  2. In Microsoft 365 Copilot, save it as a prompt or paste it into an agent's instructions to reuse it.

Any other assistant

  1. Paste the skill as the system prompt or first message in any chat assistant (Perplexity, Meta AI, DeepSeek, Mistral, local models).
  2. Coding agents that read the Agent Skills format (SKILL.md) can load the downloaded file from their skills folder.

Install it permanently

Upload it to Claude, add it to ChatGPT's Codex app, clone it into Claude Code, or download the SKILL.md for any agent. Full guide with screenshots →

Download the ZIP and upload it in Claude. Claude then uses the skill on its own whenever a request matches.

Download ZIP

Quick setup

  1. In Claude, open Settings → Skills (under Customize).
  2. Click Add → Upload skill.
  3. Choose the ZIP — don't unzip it — and make sure the skill is switched on.
Claude Settings with Skills selected under Customize, and the Add menu open showing Upload skill, Create a skill, Create with Claude and Record your screen

Repositoryscienceofapps.com/skills/ai-skills.git · all 200 skills, one folder each, plain git over HTTPS

What it does

The steps it follows

  1. Lay out required invoice fields.
  2. Work out intra-state (CGST + SGST) or inter-state (IGST) from the states given.
  3. Calculate tax and totals, showing the maths.
  4. Add the amount in words and declarations.
What you get back

The reply format

  • Invoice (table layout)
  • Tax calculation
  • Fields to check

Rules it never breaks

  • This prepares an invoice; confirm rates and SAC codes with your CA.
  • Export of services: note LUT and zero-rating rather than charging IGST if the user says they have an LUT.
  • Uses only the facts you give it and marks assumptions.
FAQs

Questions about GST invoice drafter

What does the GST invoice drafter skill do?

Freelancers and small businesses make GST invoice mistakes that cause compliance problems. The skill fixes that: a GST invoice layout with all required fields and correctly split CGST/SGST or IGST.

How do I install GST invoice drafter in ChatGPT, Claude or Gemini?

Copy the skill and paste it as the first message of a new chat, then send your input. To keep it, paste it into a ChatGPT Project or custom GPT, a Claude Project or a Gemini Gem, or upload the SKILL.md file as a Claude Skill.

What do I send GST invoice drafter after installing it?

Send your details and GSTIN, client details and state, services or goods with SAC/HSN, amounts and date. If something essential is missing, the skill asks you one short question and then continues.

Is the GST invoice drafter skill free?

Yes. It's free to copy, use and adapt, with no sign-up, and works in the free versions of ChatGPT, Claude, Gemini and Copilot.

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