Canadian ACB and Capital Gains MCP server

This is a helper for people who invest in a regular Canadian taxable account and have to report capital gains. It lets your AI do the math on your trades: average cost, gains per sale, and the tricky 30-day superficial loss rule. Handy if you have a pile of buy and sell rows and no wish to fight a spreadsheet.

What this MCP server does

You give your AI a list of trades, either typed out or as a CSV or JSON file. The AI passes them to this helper. The helper pools all the buys and sells of the same ticker, works out your average cost per share, and figures the gain or loss on each sale. It also checks for superficial losses, where a loss is denied because you bought the same security again within 30 days. Then it hands back a clean summary you can read in the chat.

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What you can do with it

• Calculate your adjusted cost base and capital gains from a list of trades
• Get a Schedule 3 style report for one tax year
• See your current holdings and their book cost
• Check whether any sales triggered a superficial loss
• Work out unrealized gains against market prices you supply
• Clean up a raw broker CSV export before running the numbers

Try asking your AI

• “Calculate the ACB and capital gains for the trades in my trades.csv file”
• “What's my capital gains report for 2024?”
• “Did any of these sales trigger a superficial loss?”
• “XEQT is at $35.20 and VTI at $305.40 USD with a 1.37 exchange rate, what are my unrealized gains?”

What it gives back to you

You get structured numbers back in the chat: your current holdings with shares and total cost, each sale with its proceeds, cost, and gain, and a yearly summary with your net and taxable capital gain. It also flags any superficial losses and shows the denied amount. If a row in your file could not be used, it tells you why.

Before you start

Who it's for

Canadian do-it-yourself investors and anyone who files their own capital gains on a taxable account.