The calculator that is not advice

The startup idea

The problem

Most guides quote 0.1% and the round trip is closer to 0.23%.

Who would pay for this?

Primary

Someone who already uses Claude Code and trades NSE or BSE.

Secondary

A person who will confirm a tax answer with a professional.

Early adopter

One charges run, the disclaimer visible.

How could it make money?

Possible models. Nothing here is a claim about what India Trading Skills charges.

• No price. MIT.
• A broker MCP is optional and billed by the broker.
• The post says free.

What would the MVP look like?

1. 23 skills, or one calculator.
2. The 0.23% line.
3. The not-advice disclaimer.
4. Optional broker login, labeled optional.

How to validate the idea

• Ask five people whether the skill told them to buy.
• If it did, the disclaimer failed.
• Do not ship a number from a US guide.

How to differentiate

• It is Indian charges, not a US template.
• 91% is printed.
• It does not place the trade.
• Do not become a broker.

Product that inspired this idea

Shubham's post says 23 free, open-source Claude Code skills for NSE, BSE, NIFTY F&O, Indian taxation, and trading costs. Ten calculators. 200 tests. The repository is Shubhamkumartrichy/claude-trading-skills-india. The license is MIT. The readme says a delivery round trip costs about 0.23% to break even, not the 0.1% most guides quote. After the April 2026 STT hike, a NIFTY futures lot needs about 14 points just to cover charges. The disclaimer says these are educational tools, not investment, trading, or tax advice, and not from a SEBI-registered adviser. It cites SEBI's finding that about 91% of individual F&O traders lost money in FY25. Live broker data is optional, through an MCP login. The post does not print the 91% line, or the not-advice line. This page did not run a calculator.

Posted by @TheTortAndHare. Watch the original launch. No separate product site is listed unless the post itself is the source.

• claude
• markets

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